Дисертації: "Primary Heat Transfer System"

1

FROIO, ANTONIO. "Multi-scale thermal-hydraulic modelling for the Primary Heat Transfer System of a tokamak." Doctoral thesis, Politecnico di Torino, 2018. http://hdl.handle.net/11583/2704378.

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The EU DEMO reactor is currently in its pre-conceptual design phase by the EUROfusion Consortium members; it aims to be the first tokamak fusion reactor to demonstrate the capability to produce net electrical energy from fusion reactions. To this aim, it must prove tritium self-sufficiency, and so it will be the first tokamak to include a Breeding Blanket (BB), to breed tritium exploiting lithium and the neutrons coming from the fusion reactions. Moreover, to prove feasibility of fusion electricity, the EU DEMO reactor will also be the first to include the power conversion chain, converting the heat coming from fusion reactions into electrical energy, through a Primary Heat Transfer System, which removes the heat deposited in the components close to the plasma and delivering it to the Power Conversion System, that, in the end, produces electricity. Within this framework, a new computational tool is developed, supported by the EUROfusion Programme Management Unit. This code, called the GEneral Tokamak THErmal-hydraulic Model (GETTHEM), aims at fast, system-level, transient thermal-hydraulic modelling of the EU DEMO Primary Heat Transfer System and Balance-of-Plant (BoP), including all the in-vessel and ex-vessel cooling components, and it is the first system-level code of this type explicitly developed for fusion applications. The thermal-hydraulic models of the in-vessel components are developed, starting from the BB, as it is the most thermally loaded component and, consequently, the most important for the BoP. The GETTHEM development currently focuses on two out of the four BB concepts studied in the EU, namely the Helium-Cooled Pebble Bed (HCPB) and the Water-Cooled Lithium-Lead (WCLL) BB concepts. Considering that the EU DEMO is still in pre-conceptual design, the code focuses on execution speed, while maintaining an acceptable accuracy, typically modelling the different components as 0D/1D interconnected objects. GETTHEM is applied to analyse the coolant distribution in the HCPB BB, as well as the maximum temperature reached under normal operating condition in the structural material of both BB concepts, which must stay below 550 °C as a safety requirement. The model is capable to highlight if and where the coolant distribution in the HCPB BB should be optimized in order to avoid an overheating of the structures, allowing at the same time to reduce the compression power needed to circulate the coolant. It also can show if in some regions of the BB, for both coolant options, more detailed analyses are needed, as the current design, tailored on the equatorial BB region, somehow penalizes the regions far from the equatorial plane. Moreover, a separate module of the code is developed, aiming, through suitable simplifications, at fast modelling of accidental transients such as in-vessel Loss-Of-Coolant Accidents (LOCAs). Such module of the code is applied to the parametric analysis of an in-vessel LOCA for HCPB and WCLL, exploiting the code speed to rapidly screen the effect, for instance, of different break sizes, contributing to the proper sizing of the Vacuum Vessel Pressure Suppression System.

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2

Parker, Gregory K. "Heat transfer parametric system identification." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1993. http://handle.dtic.mil/100.2/ADA268525.

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3

Okorafor, Agbai Azubuike. "A study of heat and mass transfer in a double-diffusive system /." Available from the University of Aberdeen Library and Historic Collections Digital Resources. Restricted: no access until May 13, 2009, 2009. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=26048.

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4

Miller, Mark W. "Heat transfer in a coupled impingement-effusion cooling system." Master's thesis, University of Central Florida, 2011. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4807.

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The efficiency of air-breathing gas turbine engines improves as the combustion temperature increases. Therefore, modern gas turbines operate at temperatures greater than the melting temperature of hot-gas-path components, and cooling must be introduced in order to maintain mechanical integrity of those components. Two highly effective techniques used in modern designs for this purpose are impingement cooling and use of coolant film on hot-gas-path surface introduced through discrete film or effusion holes. In this study, these two mechanisms are coupled into a single prototype cooling system. The heat transfer capability of this system is experimentally determined for a variety of different geometries and coolant flow rates. This study utilizes Temperature Sensitive Paint (TSP) in order to measure temperature distribution over a surface, which allowed for local impingement Nusselt number, film cooling effectiveness, and film cooling heat transfer enhancement profiles to be obtained. In addition to providing quantitative heat transfer data, this method allowed for qualitative investigation of the flow behavior near the test surface. Impinging jet-to-target-plate spacing was varied over a large range, including several tall impingement scenarios outside the published limits. Additionally, both in-line and staggered effusion arrangements were studied, and results for normal injection were compared to full coverage film cooling with inclined- and compound-angle injection. Effects of impingement and effusion cooling were combined to determine the overall cooling effectiveness of the system. It is shown that low impingement heights produce the highest Nusselt number, and that large jet-to-jet spacing reduces coolant flow rate while maintaining moderate to high heat transfer rates. Staggered effusion configurations exhibit superior performance to in-line configurations, as jet interference is reduced and surface area coverage is improved. Coolant to mainstream flow mass flux ratios greater than unity result in jet blow-off and reduced effectiveness. The convective heat transfer coefficient on the film cooled surface is higher than a similar surface without coolant injection due to the generation of turbulence associated with jet-cross flow interaction.
ID: 030646180; System requirements: World Wide Web browser and PDF reader.; Mode of access: World Wide Web.; .; Thesis (M.S.M.E.)--University of Central Florida, 2011.; Includes bibliographical references (p. 171-176).
M.S.M.E.
Masters
Mechanical and Aerospace Engineering
Engineering and Computer Science
Mechanical Engineering; Thermo-Fluids Track

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5

Tetlow, David. "Heat transfer enhancement in integrated phase change drywall system." Thesis, Nottingham Trent University, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.446610.

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6

Thuppal, Vedanta Srivatsan, and Naga Vamsi Krishna Kora. "HEAT TRANSIENT TRANSFER ANALYSIS OF BRAKE DISC /PAD SYSTEM." Thesis, Blekinge Tekniska Högskola, Institutionen för maskinteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-13461.

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Braking is mainly controlled by the engine. Friction between a pair of pads and a rotating disc converts the kinetic energy of the vehicle into heat. High temperatures can be reached in the system which can be detrimental for both, components and passenger safety. Numerical techniques help simulate load cases and compute the temperatures field in brake disc and brake pads. The present work implements a Finite Element (FE) toolbox in Matlab/Simulink able to simulate different braking manoeuvres used for brake dimensioning mainly in the early phase of car development process. The brake pad/disc geometry is considered as an axisymmetric body assuming negligible temperature gradient along the circumference of the disc. Calibration using three control factors namely: heat coefficient during braking , acceleration and emissivity for the implemented thermal model is performed using experimental investigation at Volvo Car Corporation (VCC) for three specific severe load cases. The thermal model is extended to measure brake fluid temperatures to ensure no vaporisation occurs. Simulation results of the brake disc and brake pad show good correlation with the experimental tests. A sensitivity analysis with the control factors showed convective coefficient during acceleration the most sensitive, with temperature change of around 16%.

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7

Rajab, Ahmed Dawod A. "Heat transfer study of an immersed horizontal tube desalination system." Thesis, University of Liverpool, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240806.

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8

Anzalone, Thomas M. "Heat transfer characteristics of a fluidized bed : stirling engine system." The Ohio State University, 1989. http://rave.ohiolink.edu/etdc/view?acc_num=osu1291128389.

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9

Fiala, Dusan. "Dynamic simulation of human heat transfer and thermal comfort." Thesis, Online version, 1998. http://ethos.bl.uk/OrderDetails.do?did=1&uin=uk.bl.ethos.340123.

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10

Moss, Michael Andrew. "A knowledge based database system for jet impingement heat transfer correlations." Thesis, Nottingham Trent University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334747.

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11

Fenton, Marcus Brian Mayhall. "Flow and heat transfer modelling of an automotive engine lubrication system." Thesis, University of Warwick, 1994. http://wrap.warwick.ac.uk/3494/.

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This dissertation documents the thermodynamic and fluid mechanic analysis of an engine lubrication system. A comprehensive thermofluid computer model was developed to provide a flexible design analysis tool for the accurate prediction of oil pressures, flow rates and temperatures at any point within any lubrication system. Technical and financial support for the study was provided by Jaguar Cars. A comprehensive literature review revealed that the past research in this field had concentrated on either the thermofluid analysis of the lubrication system by engine testing, or the detailed analysis of individual components. A small number of computer models were developed for the flow analysis of the whole lubrication system. However, these models had limited heat transfer prediction capabilities, some requiring measured engine temperature data, and were not flexible enough to be employed as design tools. The objective of this study was to develop a flexible steady-state thermofluid design analysis tool, by integrating a flow analysis approach with a detailed analysis of the heat transfer within the engine block. Mathematical models of the thermofluid behaviour of the lubrication system components were developed and were implemented in a suite of FORTRAN computer programs which formed the design analysis package. A simple, linear flow model was initially developed to represent the system with a combination of laminar pipes, pumps, filters, journal bearings, crank-shaft transfer holes and cam bearing transfer holes. The linear program provided a rapid analysis tool, but the accuracy of the results were limited by the simplified flow characteristics of the system components. A more comprehensive and flexible non-linear flow model was developed, which solved for the unknowns with an iterative technique. Additional component models with non-linear flow characteristics, such as turbulent pipes, annular pipes, strainers, and oil coolers, were developed. The non-linear solution technique was proven to be robust and flexible and was subsequently used in all the analysis programs. The heat transfer to the oil within the pressurised part of the lubrication system is modelled by the heat transfer program. The engine block temperatures are calculated by the engine block program. This program accounts for the heat transfer to the oil splashed on to the internal surfaces of the engine. The engine geometry is represented by a series of block elements and modelled as a nodal resistance network. This capability has particular importance during the design stage, rapidly providing an estimate of the temperature profile through the engine block, results which were previously only available from expensive and slow FEA models. It was shown that both the Jaguar AJ6 and V8 engine lubrication systems could be analyzed in great detail. Engine tests showed that the predicted flow rates, pressures and temperatures were in excellent agreement with measured values. The overall accuracy of the results induced a high degree of confidence in the thermofluid model. The final analysis package was proven to be easy to use, robust, rapid, flexible and accurate. The design analysis package, developed during the course of this study, represents a unique stand-alone simulation tool which can rapidly analyze any engine lubrication system configuration. This package provides a valuable analysis tool which can be used to optimise system designs at the initial design stage and the diagnosis of performance problems during the development phase. Parametric studies can be easily carried out on the lubrication system and engine block configuration to identify areas which can enhance heat transfer to the oil. The steady-state analysis package forms an excellent platform for the development of a full transient model. This would allow a detailed analysis of the lubrication system during engine warm-up, with the aim of reducing engine emissions and determining minimum oil requirements.

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12

Gord, Mahmoud Farzaneh. "Flow and heat transfer in a pre-swirl rotor-stator system." Thesis, University of Bath, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.288236.

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This thesis describes the computational study of the flow and heat transfer in a directtransfer pre-swirl rotor-stator system. Pre-swirl cooling air enters the system at low radius through angled pre-swirl nozzles, located on the stator, impinges on the rotor and flows outward in the wheel-space between stator and rotor, and leaves the system through receiver holes, located on the rotor. Computations were carried out using a 3D incompressible model, with one discrete pre-swirl nozzle on the stator and cyclic symmetry boundary conditions applied at the tangential faces of the domain. To permit steady-state computations, an annular outlet was used on the rotor that matched the centerline radius and total area of the receiver holes. The Reynolds-averaged Navier-Stokes equations in cylindrical polar coordinates were solved in primitive-variables using the finite-volume method, hybrid differencing and the SIMPLE pressure-correction scheme. The low-Reynolds-number Launder-Sharma turbulence model was used primarily and the Morse k-c model was also tested. An axisymmetric numerical investigation was conducted to study the effect of the swirl ratio and other flow parameters on the flow and heat transfer in system, with computation times reduced by a factor of around 7 compared with the corresponding 3D computations. The computations were also compared with data obtained from a complementary experimental study. The range of flow parameters tested in the experiments and used in the computations were: for rotational Reynolds numbers, 0.77 x 106 < Red, < 1.2 x 106; for non-dimensional pre-swirl flow rates, 0.6 X 104 < Cw'P < 2.8 x 104 (giving 0.12 AT, p = cw, pReoe'8 < 0.4); for pre-swirl ratio, 0.5 < /3p < 3. The computed and measured values of (tangentially-averaged) non-dimensional tangential velocity, VO/Str, and static and total pressure coefficient are mainly in good agreement. The computed results suggest that free-vortex flow occurs between the pre-swirl inlets and the receiver outlet. The results show a significant loss in total pressure near the pre-swirl inlets. An expression has been derived for calculating the discharge coefficient for the receiver outlet, and there is good agreement between measured and computed values The computed local Nusselt number, Nu, is compared with measured values. There is reasonably good agreement between computation and measurement for the level of Nu apart from the impingement region and radially outward of the receiver outlet. There is a large peak in Nu near the inlet radius, due the behaviour of the low-Reynolds number turbulence model in the impingement region. The measured effects of Red, AT, p and ßp on the level of Nu are reproduced well by the computations.

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13

Karabay, Hasan. "Flow and heat transfer in cover-plate pre-swirl rotor-stator system." Thesis, University of Bath, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242797.

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14

Khaliji, Oskouei Mohammadhasan. "Thermodynamic and heat transfer analysis of an activated carbon-R723 adsorption system." Thesis, University of Warwick, 2016. http://wrap.warwick.ac.uk/95081/.

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The main challenge of adsorption systems today is to improve the performance of the thermal generator in order to make adsorption systems economically viable. The key novelty of this doctoral thesis is its evaluation of the potential use of a new refrigerant, R723, in an adsorption system using activated carbon as adsorbent. Granular activated carbon is a well-known and effective adsorbent in adsorption systems. The R723 refrigerant was introduced into the market in early 2004; this new refrigerant is an azeotropic mixture of 40% ammonia and 60% dimethyl ether by mass. The new refrigerant is compatible with copper alloy (Cu-Ni 90/10), in comparison with ammonia, which is only compatible with stainless steel. The high thermal conductivity of Cu-Ni 90/10 causes an improvement in heat exchange in the thermal generator. This work investigates the effect of granular activated carbon packed bed density on gas permeability. A correlation was found between granular activated carbon packing density and refrigerant pressure drop over the thermal generator. The porosity of granular activated carbon in terms of adsorbing the R723 was determined. The porosity was evaluated using the gas mixture adsorption theory and using the porosity experimental data for granular activated carbon / ammonia and granular activated carbon / dimethyl ether pairs. The performance of the adsorption system for different applications was determined with the activated carbon / R723 pair. The effects of concentration of R723 and granular activated carbon packing density on the thermal parameters of activated carbon packing, including the thermal conductivity and heat transfer coefficients of the contact wall/packed carbon, were studied simultaneously. A correlation was established showing the connection between the thermal parameters of the packed bed, and the concentration of R723 and the density of the granular activated carbon packed bed. Finally, this thesis demonstrates modelling procedures for a tubular generator with the granular activated carbon (208-C) / R723 pair, with regard to different applications such as air conditioning, ice making and a heat pump. The model under consideration included the ideal desorption effect without heat and mass recovery, while imposing the ideal temperature jump into the boundary of the tubular generator. During the modelling, information such as driving temperature (Tg), coefficient of performance (COP), and specific cooling and heating powers (SCP & SHP), was collected. The collected information was used to established a correlation in order to estimate the optimum driving temperature, COP, SHP and SCP, based on different governing parameters, such as granular activated carbon packing density, outside diameter (OD) and the length of the thermal generator. This information is useful in choosing the correct typical standard tube size of the thermal generator with the granular activated carbon (208-C) / R723 pair for specific applications, based on optimum governing parameters, such as the range of heat source availability and the power requirement. The other key point which was examined was the effect of tubular generator body material on COP and SCP (SHP) for different applications. The model used stainless steel and Cu-Ni 90/10 with standard wall thickness.

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15

Zhai, Qiang. "A NUMERICAL STUDY OF A HEAT EXCHANGER SYSTEM WITH A BYPASS VALVE." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1461252171.

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16

Liu, Lei. "Heat transfer from a convecting crystallizing, replenished magmatic sill and its link to seafloor hydrothermal heat output." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/37215.

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Hydrothermal systems at oceanic spreading centers play an important role in the composition of seawater, the formation of ore deposits, the support of microbial and macrofaunal ecosystems, and even for the development of life on early earth. These circulation systems are driven by heat transport from the underlying magma chamber, where latent heat of crystallization and sensible heat from cooling are transferred by vigorous, high Rayleigh number convection through a thin conductive boundary layer. The traditional study of magmatic-hydrothermal systems is primarily based on the time-series observation, which takes the form of repeat visits, continuous offline monitoring by autonomous instruments, or continuous online monitoring by instruments with satellite or cable links to shore. Although a number of studies have deployed autonomous monitoring instruments at vents and around mid-ocean ridges to investigate geophysical and hydrothermal processes, the data are still rather limited and a comprehensive understanding of magma-hydrothermal processes at oceanic spreading centers is lacking. Numerical modeling needs to be employed to elucidate the dynamic behavior of magmatic hydrothermal systems and for testing completing hypotheses in these complex, data-poor environments. In this dissertation, I develop a mathematical framework for investigating heat transport from a vigorously convecting, crystallizing, cooling, and replenished magma chamber to an overlying hydrothermal system at an oceanic spreading center. The resulting equations are solved numerically using MATLAB. The simulations proceed step-by-step to investigate several different aspects of the system. First, I consider a hydrothermal system driven by convection, cooling and crystallization in a ~ 100 m thick basaltic magma sill representing an axial magma chamber (AMC) at an oceanic spreading center. I investigate two different crystallization scenarios, crystal-suspended and crystal-settling, and consider both un-replenished and replenished AMCs. In cases without magma replenishment, the simulation results for crystals-suspended models show that heat output and the hydrothermal temperature decrease rapidly and crystallinity reaches 60% in less than ten years. In crystals-settling models, magma convection may last for decades, but decreasing heat output and hydrothermal temperatures still occur on decadal timescales. When magma replenishment is included, the magmatic heat flux approaches steady state on decadal timescales, while the magma body grows to double its original size. The rate of magma replenishment needed ranges between 5 x 10⁵ and 5 x 10⁶ m³/yr, which is somewhat faster than required for seafloor spreading, but less than fluxes to some terrestrial and subseafloor volcanoes on similar timescales. The heat output from a convecting, crystallizing, replenished magma body that is needed to drive observed high-temperature hydrothermal systems is consistent, with gabbro glacier models of crustal production at mid-ocean ridges. Secondly, I study the heat transfer model from a parametric perspective and examine the effects of both initial magma chamber thickness and magma replenishment rate on the hydrothermal heat output. The initial rate of convective heat transfer is independent of the initial sill thickness; but without magma replenishment, the rate of decay of the heat output varies linearly with thickness, resulting in short convective lifetimes and decaying hydrothermal temperatures for sills up to ~ 100m thick. When magma replenishment is included in crystals settling scenarios at constant or exponentially decreasing rates of ~ 10⁻⁸ m/s to the base of the sill, growth of the sill results in stabilized heat output and hydrothermal temperature on decadal timescales and a relatively constant to increasing thickness of the liquid layer. Sills initially ~ 10 m thick can grow, in principal, to ~ 10 times their initial size with stable heat output and a final melt thickness less than 100m. Seismic data provides evidence of AMC thickness, but it can not discriminate whether it denotes initial magma thickness or is a result of replenishment. These results suggest that magma replenishment might not be seismically detectable on decadal time scales. Periodic replenishment may also result in quasi-stable heat output, but the magnitude of the heat output may vary considerably in crystals suspended models at low frequencies; compared to crystals settling models. In these models the direct coupling between magmatic and hydrothermal heat output suggests that heat output fluctuations might be recorded in hydrothermal vents; but if damping effects of the basal conductive boundary layer and the upflow zone are taken into account, it seems unlikely that heat output fluctuations on a time scale of years would be recorded in hydrothermal vent temperatures or heat output. Thirdly, I extend the work to the binary system motivated by the fact that the real magmas are multi-component fluids. I focus on the extensively studied binary system, diopside-anorthite (Di-An), and investigate the effects of convection of a two-component magma system on the hydrothermal circulation system through the dynamic modeling of both temperature and heat output. I model the melt temperature and viscosity as a function of Di concentration, and incorporate these relations in the modeling of the heat flux. Simulations comparing the effects of different initial Di concentrations indicate that magmas with higher initial Di concentrations convect more vigorously, which results in faster heat transfer, more rapid removal of Di from the melt and growth of crystals on the floor. With magma replenishment, I assume that the magma chamber grows either horizontally or vertically. In either case magma replenishment at a constant rate of ~ 10⁻⁸ m³/a can maintain relatively stable heat output of 10⁷-10⁹ Watts and reasonable hydrothermal vent temperatures for decades. The final stabilized heat flux increases with increasing Di content of the added magma. Periodic replenishment with a 10 year period results in temperature perturbations within the magma that also increase as a function of increasing Di. With the simple magma model used here, one can not discern conclusively whether the decrease in magma temperature between the 1991/1992 and the 2005/2006 eruptions at EPR 9°50'N involved replenishment with more or less evolved magmas. Fourthly, I investigate a high-silica magma chamber as the hydrothermal circulation driver. I construct viscosity models for andesite and dacite melts as a function of temperature and water content and incorporate these expressions into a numerical model of thermal convective heat transport from a high Rayleigh number, well-mixed, crystallizing and replenished magma sill beneath a hydrothermal circulation system. Simulations comparing the time dependent heat flux from basalt, 0.1wt.% andesite, 3wt.% andesite, and 4wt.% dacite, indicate that higher viscosity magmas convect less vigorously, which results not only in lower heat transport and hydrothermal vent temperatures, but also in a lower decay rate of the vent temperature. Though somewhat colder, hydrothermal systems driven by unreplenished high-silica melts tend to have a longer lifetime than those driven by basalts, assuming a heat output cutoff of 10⁷ Watts. As in the basaltic case, magma replenishment at a rate of ~ 3 x 10⁵ - 3 x 10⁶ m³/a can maintain relatively stable heat output of 10⁷-10⁹ Watts and hydrothermal vent temperatures for decades. Idealized models of porous flow through the lower crust suggest such replenishment rates are not likely to occur, especially for high-viscosity magmas such as andesite and dacite. Long term stability of hydrothermal systems driven by these magmas requires an alternate means of magma replenishment. Finally, the dissertation concludes by discussing some avenues for future work. Most important of these are to: (1) couple magma convection with more realistic hydrothermal models and (2) link magma chamber processes to better physical models of replenishment and eruption.

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17

Glover, Garrett A. "The Next Generation Router System Cooling Design." DigitalCommons@CalPoly, 2009. https://digitalcommons.calpoly.edu/theses/191.

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Advancements in the networking and routing industry have created higher power electronic systems which dissipate large amounts of heat while cooling technology for these electronic systems has remained relatively unchanged. This report illustrates the development and testing of a hybrid liquid-air cooling system prototype implemented on Cisco’s 7609s router. Water was the working fluid through cold plates removing heat from line card components. The water was cooled by a compact liquid-air heat exchanger and circulated by two pumps. The testing results show that junction temperatures were maintained well below the 105°C limit for ambient conditions around 30°C at sea level. The estimated junction temperatures for Cisco’s standard ambient conditions of 50°C at 6,000 feet and 40°C at 10,000 feet were 104°C and 96°C respectively. Adjustments to the test data for Cisco’s two standard ambient conditions with expected device characteristics suggested the hybrid liquid-air cooling design could meet the projected heat load.

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18

Smith, Brandon. "Simulation of Heat/Mass Transfer of a Three-Layer Impingement/Effusion Cooling System." Master's thesis, University of Central Florida, 2012. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5509.

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Cooling techniques for high density electrical components and electronic devices have been studied heavily in recent years. The advancements in the electrical/electronic industry have required methods of high heat flux removal. Many of the current electrical components and electronic devices produce a range of heat fluxes from 20 W/cm2 – 100 W/cm2. While parallel flow cooling systems have been used in the past, jet impingement is now more desirable for its potential to have a heat transfer coefficient 3-5 times greater than that of parallel flow at the same flow rate. Problems do arise when the jet impingement is confined and a cross flow develops that interacts with impinging jets downstream leading to a decrease in heat transfer coefficient. For long heated surfaces, such as an aircraft generator rotor, span wise fluid management is important in keeping the temperature distribution uniform along the length of the surface. A detailed simulation of the heat/mass transfer on a three-layer impingement/effusion cooling system has been conducted. The impingement jet fluid enters from the top layer into the bottom layer to impinge on the heated surface. The spent fluid is removed from the effusion holes and exits through the middle layer. Three different effusion configurations were used with effusion diameters ranging from 0.5 mm to 2 mm. Temperature uniformity, heat transfer coefficients, and pressure drops were compared for each effusion diameter arrangement, jet to target spacing (H/d), and rib configuration. A Shear Stress Transport (SST) turbulence fluid model was used within ANSYS CFX to simulate all design models. Three-layer configurations were also set in series for long, rectangular heated surfaces and compared against traditional cooling methods such as parallel internal flow and traditional jet impingement models. The results show that the three-layer design compared to a traditional impingement cooling scheme over an elongated heated surface can increase the average heat transfer coefficient by 75% and reduce the temperature difference on the surface by 75%. It was shown that for a three layer design under the same impingement geometry, the average heat transfer coefficient increases when H/d is small. The inclusion of ribs always provided better heat transfer and centralized the cooling areas. The heat transfer was increased by as much as 25% when ribs were used. The effusion hole arrangement showed minimal correlation to heat transfer other than a large array provides better results. The effusion holes' greatest impact was found in the pressure drop of the cooling model. The pressure losses were minimal when the effective area of effusion holes was large. This minimizes the losses due to contraction and expansion.
M.S.M.E.
Masters
Mechanical and Aerospace Engineering
Engineering and Computer Science
Mechanical Engineering; Thermofluids

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19

Gdhaidh, Farouq Ali S. "Heat transfer characteristics of natural convection within an enclosure using liquid cooling system." Thesis, University of Bradford, 2015. http://hdl.handle.net/10454/7824.

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In this investigation, a single phase fluid is used to study the coupling between natural convection heat transfer within an enclosure and forced convection through computer covering case to cool the electronic chip. Two working fluids are used (water and air) within a rectangular enclosure and the air flow through the computer case is created by an exhaust fan installed at the back of the computer case. The optimum enclosure size configuration that keeps a maximum temperature of the heat source at a safe temperature level (85°C) is determined. The cooling system is tested for varying values of applied power in the range of 15-40W. The study is based on both numerical models and experimental observations. The numerical work was developed using the commercial software (ANSYS-Icepak) to simulate the flow and temperature fields for the desktop computer and the cooling system. The numerical simulation has the same physical geometry as those used in the experimental investigations. The experimental work was aimed to gather the details for temperature field and use them in the validation of the numerical prediction. The results showed that, the cavity size variations influence both the heat transfer process and the maximum temperature. Furthermore, the experimental results ii compared favourably with those obtained numerically, where the maximum deviation in terms of the maximum system temperature, is within 3.5%. Moreover, it is seen that using water as the working fluid within the enclosure is capable of keeping the maximum temperature under 77°C for a heat source of 40W, which is below the recommended electronic chips temperature of not exceeding 85°C. As a result, the noise and vibration level is reduced. In addition, the proposed cooling system saved about 65% of the CPU fan power.

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20

Gdhaidh, Farouq A. S. "Heat Transfer Characteristics of Natural Convection within an Enclosure Using Liquid Cooling System." Thesis, University of Bradford, 2015. http://hdl.handle.net/10454/7824.

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In this investigation, a single phase fluid is used to study the coupling between natural convection heat transfer within an enclosure and forced convection through computer covering case to cool the electronic chip. Two working fluids are used (water and air) within a rectangular enclosure and the air flow through the computer case is created by an exhaust fan installed at the back of the computer case. The optimum enclosure size configuration that keeps a maximum temperature of the heat source at a safe temperature level (85℃) is determined. The cooling system is tested for varying values of applied power in the range of 15−40𝑊. The study is based on both numerical models and experimental observations. The numerical work was developed using the commercial software (ANSYS-Icepak) to simulate the flow and temperature fields for the desktop computer and the cooling system. The numerical simulation has the same physical geometry as those used in the experimental investigations. The experimental work was aimed to gather the details for temperature field and use them in the validation of the numerical prediction. The results showed that, the cavity size variations influence both the heat transfer process and the maximum temperature. Furthermore, the experimental results ii compared favourably with those obtained numerically, where the maximum deviation in terms of the maximum system temperature, is within 3.5%. Moreover, it is seen that using water as the working fluid within the enclosure is capable of keeping the maximum temperature under 77℃ for a heat source of 40𝑊, which is below the recommended electronic chips temperature of not exceeding 85℃. As a result, the noise and vibration level is reduced. In addition, the proposed cooling system saved about 65% of the CPU fan power.

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21

Nabati, Hamid. "Numerical Analysis of Heat Transfer and Fluid Flow in Heat Exchangers with Emphasis on Pin Fin Technology." Doctoral thesis, Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-14409.

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One of the most important industrial processes is heat transfer, carried out by heat exchangers in single and multiphase flow applications. Despite the existence of well-developed theoretical models for different heat transfer mechanisms, the expanding need for industrial applications requiring the design and optimization of heat exchangers, has created a solid demand for experimental work and effort. This thesis concerns the use of numerical approaches to analyze and optimize heat transfer and fluid flow in power generation industry, with emphasis on pin fin technology. This research begins with a review on heat transfer characteristics in surfaces with pin fins. Different pin fins shapes with various flow boundaries were studied, and thermal and hydraulic performances were investigated. The impact of parameters such as inlet boundary conditions, pin fin shapes, and duct cross-section characteristics on both flow and heat transfer were examined. Two important applications in power generation industry were considered for this study: power transformer cooling, and condenser for CO2 capturing application in oxy-fuel power plants. Available experimental data and correlations in the literature have been used for models validation. For each case, a model based on current configuration was built and verified, and was then used for optimization and new design suggestions. All numerical modeling was performed using commercial CFD software. A basic condenser design was suggested and examined, supplemented by the use of pin fin technology to influence the condensation rate of water vapour from a CO2/H2O flue gas flow. Moreover an extensive review of numerical modeling approaches concerning this condensation issue was conducted and presented. The analysis results show that the drop-shaped pin fin configuration has heat transfer rates approximating those of the circular pin configuration, and the drop-shaped pressure losses are less than one third those of the circular. Results for the power transformer cooling system show those geometrical defects in the existing system are easily found using modeling. Also, it was found that the installation of pin fins in an internal cooling passage can have the same effect as doubling the radiator’s height, which means a more compact cooling system could be designed. Results show that a condensation model based on boundary layer theory gives a close value to experimental correlations. Considering a constant wall temperature, any increase in CO2 concentration results in lower heat transfer coefficients. This is a subsequence of increased diffusivity resistance between combustion gas and condensing boundary layer. Also it was shown that sensitivity of heat transfer rate to inlet temperatures and velocity values decreased when these parameters increased. The application of numerical methods concerning the condensation process for CO2 capturing required significant effort and running time as the complexity of multiphase flow was involved. Also data validation for the CO2/H2O condenser was challenging since this is quite a new application and less experimental data (and theoretical correlations) exist. However, it is shown that models based on numerical approaches are capable of predicting trends in the condensation process as well as the effect of the non-condensable CO2 presence in the flue gas. The resulting data, conclusions, applied methodology can be applied to the design and optimization of similar industrial heat exchangers, such as oil coolers which are currently working at low efficiency levels. It can also be used in the design of electronic components, cooling of turbine blades, or in other design applications requiring high heat flux dissipation. Finally, the finding on water vapour condensation from a binary mixture gas can be referenced for further research and development in this field.

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22

Tytarenko, A. I., D. A. Andrusenko, M. V. Isaiev, and R. M. Burbelo. "Investigation of Heat Transfer in Nanocomposite Structures “PS-liquid” Using Photoacoustic Method." Thesis, Sumy State University, 2012. http://essuir.sumdu.edu.ua/handle/123456789/35111.

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The thermal properties of porous silicon and composite «PS-liquid» system have been investigated in this paper. Using the photoacoustic method the values of thermal conductivity of porous silicon and composite systems with liquid have been obtained. It is shown that the value of thermal conductivity «PS-liquid» substantially exceeds the value determined by the model of «parallel structures». The increase of thermal conductivity is due to the improvement of thermal contacts among the crystallites when introducing liquid into the pores. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/35111

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23

Di, Ciano Massimo. "Measurement of primary region heat transfer in horizontal direct chill continuous casting of aluminum alloy re-melt ingots." Thesis, University of British Columbia, 2007. http://hdl.handle.net/2429/32372.

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Thermal-fluid modeling of the Horizontal Direct Chill (HDC) casting process has been used to aid in process optimization and development of HDC casting of aluminum foundry alloy re-melt ingots. Characterization of the heat transfer conditions present in the process is essential to accurate model development. In this study, the heat transfer conditions in the primary cooling region of an HDC casting machine were characterized using mould temperature measurements taken during plant trials. Steady state mould heat flux distributions were determined for various casting conditions through inverse heat conduction modeling. The calculated heat fluxes are of comparable magnitude to values reported in DC casting literature. Mould heat fluxes were affected by casting speed but relatively insensitive to casting temperature and mould water flow rates. To compliment the plant trial approach, an apparatus was built to replicate primary cooling region heat transfer phenomenon. Mould temperatures taken from the casting simulator were used to determine mould heat fluxes during lab tests. Comparing lab results and plant trial results confirm the applicability of the lab tests to in-plant operating conditions. These preliminary lab results suggest that use of a casting simulator could suffice as a means for characterizing primary cooling heat transfer in HDC casting, thus avoiding the need for extensive plant trials.
Applied Science, Faculty of
Materials Engineering, Department of
Graduate

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Raymond, Alexander William. "Investigation of microparticle to system level phenomena in thermally activated adsorption heat pumps." Thesis, Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/34682.

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Heat actuated adsorption heat pumps offer the opportunity to improve overall energy efficiency in waste heat applications by eliminating shaft work requirements accompanying vapor compression cycles. The coefficient of performance (COP) in adsorption heat pumps is generally low. The objective of this thesis is to model the adsorption system to gain critical insight into how its performance can be improved. Because adsorption heat pumps are intermittent devices, which induce cooling by adsorbing refrigerant in a sorption bed heat/mass exchanger, transient models must be used to predict performance. In this thesis, such models are developed at the adsorbent particle level, heat/mass exchanger component level and system level. Adsorption heat pump modeling is a coupled heat and mass transfer problem. Intra-particle mass transfer resistance and sorption bed heat transfer resistance are shown to be significant, but for very fine particle sizes, inter-particle resistance may also be important. The diameter of the adsorbent particle in a packed bed is optimized to balance inter- and intra-particle resistances and improve sorption rate. In the literature, the linear driving force (LDF) approximation for intra-particle mass transfer is commonly used in place of the Fickian diffusion equation to reduce computation time; however, it is shown that the error in uptake prediction associated with the LDF depends on the working pair, half-cycle time, adsorbent particle radius, and operating temperatures at hand. Different methods for enhancing sorption bed heat/mass transfer have been proposed in the literature including the use of binders, adsorbent compacting, and complex extended surface geometries. To maintain high reliability, the simple, robust annular-finned-tube geometry with packed adsorbent is specified in this work. The effects of tube diameter, fin pitch and fin height on thermal conductance, metal/adsorbent mass ratio and COP are studied. As one might expect, many closely spaced fins, or high fin density, yields high thermal conductance; however, it is found that the increased inert metal mass associated with the high fin density diminishes COP. It is also found that thin adsorbent layers with low effective conduction resistance lead to high thermal conductance. As adsorbent layer thickness decreases, the relative importance of tube-side convective resistance rises, so mini-channel sized tubes are used. After selecting the proper tube geometry, an overall thermal conductance is calculated for use in a lumped-parameter sorption bed simulation. To evaluate the accuracy of the lumped-parameter approach, a distributed parameter sorption bed simulation is developed for comparison. Using the finite difference method, the distributed parameter model is used to track temperature and refrigerant distributions in the finned tube and adsorbent layer. The distributed-parameter tube model is shown to be in agreement with the lumped-parameter model, thus independently verifying the overall UA calculation and the lumped-parameter sorption bed model. After evaluating the accuracy of the lumped-parameter model, it is used to develop a system-level heat pump simulation. This simulation is used to investigate a non-recuperative two-bed heat pump containing activated carbon fiber-ethanol and silica gel-water working pairs. The two-bed configuration is investigated because it yields a desirable compromise between the number of components (heat exchangers, pumps, valves, etc.) and steady cooling rate. For non-recuperative two-bed adsorption heat pumps, the average COP prediction in the literature is 0.39 for experiments and 0.44 for models. It is important to improve the COP in mobile waste heat applications because without high COP, the available waste heat during startup or idle may be insufficient to deliver the desired cooling duty. In this thesis, a COP of 0.53 is predicted for the non-recuperative, silica gel-water chiller. If thermal energy recovery is incorporated into the cycle, a COP as high as 0.64 is predicted for a 90, 35 and 7.0°C source, ambient and average evaporator temperature, respectively. The improvement in COP over heat pumps appearing in the literature is attributed to the adsorbent particle size optimization and careful selection of sorption bed heat exchanger geometry.

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Ajja, Rameshwar. "Numerical heat transfer analysis of carbon-based foams for use in thermal protection system." FIU Digital Commons, 2006. http://digitalcommons.fiu.edu/etd/1179.

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The applicability of carbon-based foams as an insulating or active cooling material in thermal protection systems (TPSs) of space vehicles is considered using a computer modeling. This study focuses on numerical investigation of the performance of carbon foams for use in TPSs of space vehicles. Two kinds of carbon foams are considered in this study. For active cooling, the carbon foam that has a thermal conductivity of 100 W/m-k is used and for the insulation, the carbon foam having a thermal conductivity of 0.225 W/m-k is used. A 3D geometry is employed to simulate coolant flow and heat transfer through carbon foam model. Gambit has been used to model the 3D geometry and the numerical simulation is carried out in FLUENT. Numerical results from this thesis suggests that the use of CFOAM and HTC carbon foams in TPS's may effectively protect the aluminum structure of the space shuttle during reentry of the space vehicle.

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Korremla, Shiva K. Sainoju. "Experimental investigation of steady state heat transfer phenomenon in Pontiac G6 vehicle exhaust system." To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2007. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.

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27

Altea, Claudinei de Moura. "Computational determination of convective heat transfer and pressure drop coefficients of hydrogenerators ventilation system." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/3/3150/tde-28092016-095253/.

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The objective of the present work is to determinate the pressure drop and the heat transfer coefficients, normally applied to analytical calculations of hydrogenerators thermal design, obtained by applying numerical calculation (Computational Fluid Dynamics - CFD) and validated by experimental results and field measurements. The object of study is limited to the most important region of the ventilation system (the cooling air ducts of stator core) to get numerical results of heat transfer and pressure drop coefficients, which are impacted mostly by the entrance of air ducts. The numerical calculations considered three-dimensional, steady-state, incompressible and turbulent flow; and were based on the Finite Volume methodology. The turbulent flow computations were carried out with procedures based on RANS equations by selecting k-omega SST (Shear-Stress Transport) as turbulence model. Grid quality metrics were monitored and the uncertainties due to discretization errors were evaluated by means of a grid independence study and application of an uncertainty estimation procedure based on Richardson extrapolation. The validation of numerical method developed by the present work (specifically to simulate the flow dynamics behavior and to obtain numerically the pressure drop coefficient of the airflow to enter and pass through the Stator Core Air Duct in a hydrogenerator) is performed by comparing the numerical results to experimental data published by Wustmann (2005). The reference experimental data were obtained by a model test. The comparison between numerical and experimental results shows that the difference of pressure drop for Reynolds numbers higher than 5000 is 2% at maximum, while for lower Reynolds numbers, the difference increases significantly and reaches 10%. It is presented that the most reasonable hypothesis for higher discrepancy at lower Reynolds numbers can be assigned to the experiment\'s non-steady-state condition. It is to conclude that the proposed numerical method is validated for the upper region of the analyzed range. Additionally to the model test validation, field measurements were executed in order to confirm numerical results. Measurements of pressure drop in the stator core of a real hydrogenerator were a challenge. Nevertheless, despite all the difficulties and considerable high field measuring uncertainties, trend curves behavior are similar to numerical results. Finally, series of numerical calculation, varying geometrical parameters of the air-duct inlet design and operational data, were done in order to obtain pressure drop coefficients trend curves to be directly applied to analytical calculation routines of whole hydrogenerator ventilation systems. Parallel to it, thermal numerical calculation was executed in the prototype simulation in order to define the convective heat transfer coefficient.
O objetivo do presente trabalho é determinar os coeficientes de perda de carga e transferência de calor, normalmente aplicados nos cálculos analíticos de design térmico de hidrogeradores, obtido pela aplicação de cálculo numérico (Computacional Fluid Dynamics - CFD) e validado por resultados experimentais e medições de campo. O objeto de estudo é limitado à região mais importante do sistema de ventilação (os dutos de ar de arrefecimento do núcleo do estator) para obter resultados numéricos dos coeficientes de transferência de calor e de perda de carga, que são impactados principalmente pela entrada de dutos de ar. Os cálculos numéricos consideraram escoamentos tridimensionais, em regime permanente, incompressíveis e turbulentos; e foram baseados no método dos volumes finitos. Os cálculos de escoamento turbulento foram realizados com procedimentos baseados em equações médias (RANS), utilizando o modelo k-omega SST (Shear-Stress Transport) como modelo de turbulência. Métricas de qualidade de malha foram monitoradas e as incertezas devido à erros de discretização foram avaliadas por meio de um estudo de independência de malha e aplicação de um procedimento de estimativa de incertezas com base na extrapolação de Richardson. A validação do método numérico desenvolvido pelo presente trabalho (especificamente para simular o comportamento dinâmico do escoamento e obter numericamente o coeficiente de perda de carga do escoamento ao entrar no duto de ar e atravessar o núcleo do estator de um hidrogerador) é realizada comparando os resultados numéricos com dados experimentais publicados por Wustmann (2005). Os dados experimentais foram obtidos como referência por um teste de modelo. A comparação entre os resultados numéricos e experimentais mostra que a diferença da perda de carga para números de Reynolds mais elevados do que 5000 é no máximo de 2%, enquanto que para números de Reynolds inferiores, a diferença aumenta significativamente e atinge 10%. A hipótese mais razoável para a maior discrepância para número de Reynolds menores é a possível influência de instabilidades do escoamento no experimento, fazendo com que o regime seja não-permanente. Conclui-se que o método numérico proposto é validado para a região superior do intervalo analisado. Além da validação pelo ensaio de modelo, medições de campo foram executadas, a fim de confirmar os resultados numéricos. As medições de perda de carga no núcleo do estator de um hidrogerador real era um desafio. No entanto, apesar de todas as dificuldades e consideráveis incertezas da medição campo, o comportamento das curvas de tendência ficou alinhado com resultados numéricos. Finalmente, uma série de cálculos numéricos, variando parâmetros geométricos do design da entrada do duto de ar e dados operacionais, foram executados a fim de se obter curvas de tendência para coeficientes de perda de carga (resultados deste trabalho) a serem aplicadas diretamente à rotinas de cálculos analíticos de sistemas completos de ventilação de hidrogeradores. Paralelamente à isso, o cálculo térmico numérico foi executado na simulação do protótipo, a fim de se definir o coeficiente de transferência de calor por convecção.

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Hatzenbuehler, Mark A. "Modeling of jet vane heat-transfer characteristics and simulation of thermal response." Thesis, Monterey, California. Naval Postgraduate School, 1988. http://hdl.handle.net/10945/23314.

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Approved for public release; distribution is unlimited
The development of a dynamic computational model capable of predicting, with the requisite design certainty, the transient thermal response of jet vane thrust control systems has been undertaken. The modeling and simulation procedures utilized are based on the concept that the thermal processes associated with jet vane operation can be put into a transfer function form commonly found in the discipline of automatic controls. Well established system identification methods are employed to formulate and verify the relationships between the various gains and frequencies of the transfer function model and experimental data provided by Naval Weapons Center, China Lake.
http://archive.org/details/modelingofjetvan00hatz
Lieutenant, United States Navy

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Krishnamurthy, Nagendra. "A Study of Heat and Mass Transfer in Porous Sorbent Particles." Diss., Virginia Tech, 2014. http://hdl.handle.net/10919/64412.

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This dissertation presents a detailed account of the study undertaken on the subject of heat and mass transfer phenomena in porous media. The current work specifically targets the general reaction-diffusion systems arising in separation processes using porous sorbent particles. These particles are comprised of pore channels spanning length scales over almost three orders of magnitude while involving a variety of physical processes such as mass diffusion, heat transfer and surface adsorption-desorption. A novel methodology is proposed in this work that combines models that account for the multi-scale and multi-physics phenomena involved. Pore-resolving DNS calculations using an immersed boundary method (IBM) framework are used to simulate the macro-scale physics while the phenomena at smaller scales are modeled using a sub-pore modeling technique. The IBM scheme developed as part of this work is applicable to complex geometries on curvilinear grids, while also being very efficient, consuming less than 1% of the total simulation time per time-step. A new method of implementing the conjugate heat transfer (CHT) boundary condition is proposed which is a direct extension of the method used for other boundary conditions and does not involve any complex interpolations like previous CHT implementations using IBM. Detailed code verification and validation studies are carried out to demonstrate the accuracy of the developed method. The developed IBM scheme is used in conjunction with a stochastic reconstruction procedure based on simulated annealing. The developed framework is tested in a two-dimensional channel with two types of porous sections - one created using a random assembly of square blocks and another using the stochastic reconstruction procedure. Numerous simulations are performed to demonstrate the capability of the developed framework. The computed pressure drops across the porous section are compared with predictions from the Darcy-Forchheimer equation for media composed of different structure sizes. The developed methodology is also applied to CO2 diffusion studies in porous spherical particles of varying porosities. For the pore channels that are unresolved by the IBM framework, a sub-pore modeling methodology developed as part of this work which solves a one-dimensional unsteady diffusion equation in a hierarchy of scales represented by a fractal-type geometry. The model includes surface adsorption-desorption, and heat generation and absorption. It is established that the current framework is useful and necessary for reaction-diffusion problems in which the adsorption time scales are very small (diffusion-limited) or comparable to the diffusion time scales. Lastly, parametric studies are conducted for a set of diffusion-limited problems to showcase the powerful capability of the developed methodology.
Ph. D.

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30

Machado, Jean Fernando Bertão. "Reynolds number effect on the heat transfer mechanisms in aircraft hot air anti-ice system." Instituto Tecnológico de Aeronáutica, 2008. http://www.bd.bibl.ita.br/tde_busca/arquivo.php?codArquivo=1158.

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The primary means of preventing ice formation on wings and engine inlets for modern commercial transport aircraft is by extracting hot air from the compressor and blowing it on the inside surface of the leading edge through small holes drilled in the so-called piccolo tube system. A critical aspect in the design of such system is the prediction of heat transfer of the impinging jets from the piccolo tube. The correct evaluation of the heat transfer rate in such devices is of great interest to optimize both the anti-icing performance and the hot air bleeding from the high-pressure compressor. The history of research in the anti-icing area is rather narrow. A review of the literature reveals that only few experimental and theoretical/numerical studies have been carried out to study the heat transfer and flow in the internal hot-air region. There are some experimental and numerical studies that developed correlations for the average Nusselt number. However, most of the research was performed using a single jet or a group of jets impinging on a flat slat, which is different from the jet impingement on concave surfaces, as the inside surface of a wing. Therefore, the objective of the present work is use the commercial CFD software FLUENT to perform a parametric study of the jet impingement on concave surfaces. The main goal is determine the effect of the Reynolds number on the heat transfer process. At the end of the work, a correlation for the average Nusselt number which account for the Reynolds number is presented.

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Garay, Rosas Ludwin. "System Simulation of Thermal Energy Storage involved Energy Transfer model in Utilizing Waste heat in District Heating system Application." Thesis, KTH, Kraft- och värmeteknologi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-161726.

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Nowadays continuous increase of energy consumption increases the importance of replacing fossil fuels with renewable energy sources so the CO2 emissions can be reduced. To use the energy in a more efficient way is also favorable for this purpose. Thermal Energy Storage (TES) is a technology that can make use of waste heat, which means that it can help energy systems to reduce the CO2 emissions and improve the overall efficiency. In this technology an appropriate material is chosen to store the thermal energy so it can be stored for later use. The energy can be stored as sensible heat and latent heat. To achieve a high energy storage density it is convenient to use latent heat based TES. The materials used in this kind of storage system are called Phase Change Materials (PCM) and it is its ability of absorbing and releasing thermal energy during the phase change process that becomes very useful. In this thesis a simulation model for a system of thermal energy transportation has been developed. The background comes from district heating systems ability of using surplus heat from industrials and large scale power plants. The idea is to implement transportation of heat by trucks closer to the demand instead of distributing heat through very long pipes. The heat is then charged into containers that are integrated with PCM and heat exchangers. A mathematical model has been created in Matlab to simulate the system dynamics of the logistics of the thermal energy transport system. The model considers three main parameters: percentage content of PCM in the containers, annual heat demand and transport distance. How the system is affected when these three parameters varies is important to visualize. The simulation model is very useful for investigation of the economic and environmental capability of the proposed thermal energy transportation system. Simulations for different scenarios show some expected results. But there are also some findings that are more interesting, for instance how the variation of content of PCM gives irregular variation of how many truck the system requires, and its impact on the economic aspect. Results also show that cost for transporting the heat per unit of thermal energy can be much high for a small demands compared to larger demands.

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Deshpande, Dhananjay D. "Computer Modeling Of A Solar Thermal System For Space Heating." Wright State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=wright1484142894264319.

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Parsons, Kevin Kenneth. "Design and Simulation of Passive Thermal Management System for Lithium-ion Battery Packs on an Unmanned Ground Vehicle." DigitalCommons@CalPoly, 2012. https://digitalcommons.calpoly.edu/theses/912.

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The transient thermal response of a 15-cell, 48 volt, lithium-ion battery pack for an unmanned ground vehicle was simulated with ANSYS Fluent. Heat generation rates and specific heat capacity of a single cell were experimentally measured and used as input to the thermal model. A heat generation load was applied to each battery and natural convection film boundary conditions were applied to the exterior of the enclosure. The buoyancy-driven natural convection inside the enclosure was modeled along with the radiation heat transfer between internal components. The maximum temperature of the batteries reached 65.6 °C after 630 seconds of usage at a simulated peak power draw of 3,600 watts or roughly 85 amps. This exceeds the manufacturer's maximum recommended operating temperature of 60 °C. The pack was redesigned to incorporate a passive thermal management system consisting of a composite expanded graphite matrix infiltrated with a phase-changing paraffin wax. The redesigned battery pack was similarly modeled, showing a decrease in the maximum temperature to 50.3 °C after 630 seconds at the same power draw. The proposed passive thermal management system kept the batteries within their recommended operating temperature range.

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Pountney, Oliver. "Modelling and measurement of sealing effectiveness and heat transfer in a rotor-stator system with ingress." Thesis, University of Bath, 2012. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.558900.

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This thesis investigates, both theoretically and experimentally, the phenomenon of ingress through gas turbine rim seals. The work presented focuses on modelling and measuring the required sealing flow levels to purge the wheelspace against combined ingress and the effect of externally-induced ingress on the surface temperature and heat transfer to the rotor. Combined ingress is driven by a pressure difference between the mainstream annulus and wheelspace cavity resulting from the combination of the asymmetric external pressure profile in the annulus and the rotation of fluid in the rotor-stator wheelspace cavity. Ingress can be prevented by pressurising the wheelspace through the supply of sealant flow. The Owen (2011b) combined ingress orifice model was solved to predict the required levels of sealant flow to prevent ingress into the wheelspace. The model was validated using prepublished data and data collected experimentally over the course of this research. Gas concentration measurements were made on the stator of the Bath single-stage gas turbine test rig to determine the variation of sealing effectiveness with sealant flow rate for an axial clearance seal geometry at design and off-design operational conditions. The measured variation of the required sealant flow rate with the ratio of the external and rotational Reynolds numbers, ReW / Reϕ, was consistent with the findings of other workers: at low values of ReW / Reϕ, ingress levels were influenced by the combined effects of the disc rotation and the annulus pressure profile and were therefore considered to fall into the combined ingress region; the influence of rotation diminished as ReW / Reϕ increased and the ingress levels were dominated by the annulus pressure field (externally-induced ingress). The orifice model was in good agreement with the experimental measurements and the prepublished experimental data. Thermochromic liquid crystal (TLC) was used to determine effect of ingress on the heat transfer coefficient, h, and adiabatic wall temperature, Tad, on the rotor of the Bath gas turbine rig. Concurrent gas concentration measurements were made on the stator to compare the effects of ingress on the two discs. Data was collected at the design condition, where ReW / Reϕ = 0.538 and at an overspeed off-design condition, where ReW / Reϕ = 0.326. The comparison between a newly defined adiabatic effectiveness, εad, on the rotor and the concentration effectiveness, εc, on the stator, showed that the rotor was protected against the effects of ingress relative to the stator. The sealing air, which is drawn into the rotor boundary layer from the source region, thermally buffers the rotor against the ingested fluid in the core. A thermal buffer ratio, η, was defined as the ratio of the minimum sealant flow required to purge the stator against ingress to the minimum sealant flow required to purge the rotor against ingress. The thermal buffer is dependent upon the flow structure in the wheelspace, which itself is governed the turbulent flow parameter, λT. A hypothesis relating η to λT was developed and shown to be in good agreement with the experimental data. The local Nusselt numbers, Nur, on the rotor were shown to be fairly constant with radius and increased as λT was increased. The latter finding can be explained by the flow structure in the wheelspace: as λT is raised, the swirl in the fluid core reduces, which results in an increase in the moment coefficient and Nur on the rotor. Difficulties in measuring Tad during the experiments suggested a new technique from which to solve for h and Tad using TLC surface temperature measurements. The solution Fourier’s equation for a step-change in the temperature of a fluid flowing over a solid of semi-infinite thickness (the ‘semi-infinite solution’) is limited to relatively low Fourier numbers if Tad is to be calculated accurately. A two-layer composite substrate made from, for example, polycarbonate and Rohacell, could be used to achieve accurate estimates of h and Tad over a larger range of Biot numbers than for a single material substrate. TLC could be used to measure the surface temperature history of the composite substrate during an experiment; this would allow h and Tad to be solved from the numerical solution of Fourier’s equation or from a combination of the semi-infinite and steady-state solutions. The work presented in this thesis has uncovered some interesting findings in areas where research was limited. The measurements of the minimum sealant flow required to purge the wheelspace at off-design operation for a rotor-stator system with blades and vanes and the measurements of the adiabatic effectiveness on a rotating disc affected by ingress are unique and provide a platform for further experimental studies and validation of CFD models.

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35

Habib, Alexander J. "A Wireless Acquisition and Control System for a High Measurement-Density, Rotating Internal Heat Transfer Experiment." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1397661589.

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36

Neuffer, Dieter. "Dynamic modelling of coal combustion on moving grates for the purpose of control system design." Thesis, University of Exeter, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341165.

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37

Lee, Sangsoo. "Development of techniques for in-situ measurement of heat and mass transfer in ammonia-water absorption systems." Diss., Available online, Georgia Institute of Technology, 2007, 2007. http://etd.gatech.edu/theses/available/etd-07082007-221833/.

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Thesis (Ph. D.)--Mechanical Engineering, Georgia Institute of Technology, 2008.
Ghiaasiaan, S. Mostafa, Committee Member ; Sheldon, M. Jeter, Committee Member ; Fuller, Tom, Committee Member ; Teja, Amyn, Committee Member ; Garimella, Srinivas, Committee Chair.

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38

Massina, Christopher James. "Characterization of dynamic thermal control schemes and heat transfer pathways for incorporating variable emissivity electrochromic materials into a space suit heat rejection system." Thesis, University of Colorado at Boulder, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10108691.

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The feasibility of conducting long duration human spaceflight missions is largely dependent on the provision of consumables such as oxygen, water, and food. In addition to meeting crew metabolic needs, water sublimation has long served as the primary heat rejection mechanism in space suits during extravehicular activity (EVA). During a single eight hour EVA, approximately 3.6 kg (8 lbm) of water is lost from the current suit. Reducing the amount of expended water during EVA is a long standing goal of space suit life support systems designers; but to date, no alternate thermal control mechanism has demonstrated the ability to completely eliminate the loss. One proposed concept is to convert the majority of a space suit’s surface area into a radiator such that the local environment can be used as a radiative thermal sink for rejecting heat without mass loss. Due to natural variations in both internal (metabolic) loads and external (environmental) sink temperatures, radiative transport must be actively modulated in order to maintain an acceptable thermal balance. Here, variable emissivity electrochromic devices are examined as the primary mechanism for enabling variable heat rejection. This dissertation focuses on theoretical and empirical evaluations performed to determine the feasibility of using a full suit, variable emissivity radiator architecture for space suit thermal control. Operational envelopes are described that show where a given environment and/or metabolic load combination may or may not be supported by the evaluated thermal architecture. Key integration considerations and guidelines include determining allowable thermal environments, defining skin-to-radiator heat transfer properties, and evaluating required electrochromic performance properties. Analysis also considered the impacts of dynamic environmental changes and the architecture’s extensibility to EVA on the Martian surface. At the conclusion of this work, the full suit, variable emissivity radiator architecture is considered to be at a technology readiness level of 3/4, indicating that analytical proof-of-concept and component level validation in a laboratory environment have been completed. While this is not a numeric increase from previous investigations, these contributions are a significant iteration within those levels. These results improve the understanding of the capabilities provided by the full suit, variable emissivity architecture.

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39

Carlsson, Carin. "Modeling and Experimental Validation of a Rankine Cycle Based Exhaust WHR System for Heavy Duty Applications." Thesis, Linköpings universitet, Fordonssystem, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-81737.

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To increase the efficiency of the engine is one of the biggest challenges for heavy vehicles. One possible method is the Rankine based Waste Heat Recovery. Crucial for Rankine based Waste Heat Recovery is to model the temperature and the state of the working fluid. If the state of the working fluid is not determined, not only the efficiency of the system could be decreased, the components of thesystem might be damaged.A Simulink model based on the physical components in a system developed by Scania is proposed. The model for the complete system is validated against a reference model developed by Scania, and the component models are further validated against measurement data. The purpose of the model is to enable model based control, which is not possible with the reference model. The main focus on the thesis is to model the evaporation and condensation to determine state and temperature of the working fluid. The developed model is compared to a reference model with little differences for while stationary operating for both the components and the complete system. The developed model also follows the behavior from measurement data. The thesis shows that two phase modeling in Simulink is possible with models based on the physical components.

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40

Pandit, Jaideep. "Numerical and Experimental Design of High Performance Heat Exchanger System for A Thermoelectric Power Generator for Implementation in Automobile Exhaust Gas Waste Heat Recovery." Diss., Virginia Tech, 2014. http://hdl.handle.net/10919/47919.

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The effects of greenhouse gases have seen a significant rise in recent years due to the use of fossil fuels like gasoline and diesel. Conversion of the energy stored in these fossil fuels to mechanical work is an extremely inefficient process which results in a high amount of energy rejected in the form of waste heat. Thermoelectric materials are able to harness this waste heat energy and convert it to electrical power. Thermoelectric devices work on the principle of the Seebeck effect, which states that if two junctions of dissimilar materials are at different temperatures, an electrical potential is developed across them. Even though these devices have small efficiencies, they are still an extremely effective way of converting low grade waste heat to usable electrical power. These devices have the added advantage of having no moving parts (solid state) which contributes to a long life of the device without needing much maintenance. The performance of thermoelectric generators is dependent on a non-dimensional figure of merit, ZT. Extensive research, both past and ongoing, is focused on improving the thermoelectric generator's (TEG's) performance by improving this figure of merit, ZT, by way of controlling the material properties. This research is usually incremental and the high performance materials developed can be cost prohibitive. The focus of this study has been to improve the performance of thermoelectric generator by way of improving the heat transfer from the exhaust gases to the TEG and also the heat transfer from TEG to the coolant. Apart from the figure of merit ZT, the performance of the TEG is also a function of the temperature difference across it, By improving the heat transfer between the TEG and the working fluid, a higher temperature gradient can be achieved across it, resulting in higher heat flux and improved efficiency from the system. This area has been largely neglected as a source of improvement in past research and has immense potential to be a low cost performance enhancer in such systems. Improvements made through this avenue, also have the advantage of being applicable regardless of the material in the system. Thus these high performance heat exchangers can be coupled with high performance materials to supplement the gains made by improved figure of merits. The heat exchanger designs developed and studied in this work have taken into account several considerations, like pressure drop, varying engine speeds, location of the system along the fuel path, system stability etc. A comprehensive treatment is presented here which includes 3D conjugate heat transfer modeling with RANS based turbulence models on such a system. Various heat transfer enhancement features are implemented in the system and studied numerically as well as experimentally. The entire system is also studied experimentally in a scaled down setup which provided data for validation of numerical studies. With the help of measured and calculated data like temperature, ZT etc, predictions are also presented about key metrics of system performance.
Ph. D.

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41

Jun, Hyoung Yoll. "Development of a fuel-powered compact SMA (Shape Memory Alloy) actuator system." Diss., Texas A&M University, 2003. http://hdl.handle.net/1969.1/1426.

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The work presents investigations into the development of a fuel-powered compact SMA actuator system. For the final SMA actuator, the K-alloy SMA strip (0.9 mm x 2.5 mm), actuated by a forced convection heat transfer mechanism, was embedded in a rectangular channel. In this channel, a rectangular piston, with a slot to accommodate the SMA strip, ran along the strip and was utilized to prevent mixing between the hot and the cold fluid in order to increase the energy density of the system. The fuel, such as propane, was utilized as main energy source in order to achieve high energy and power densities of the SMA actuator system. Numerical analysis was carried out to determine optimal channel geometry and to estimate maximum available force, strain and actuation frequency. Multi-channel combustor/heat exchanger and micro-tube heat exchanger were designed and tested to achieve high heat transfer rate and high compactness. The final SMA actuator system was composed of pumps, valves, bellows, multi-channel combustor/heat exchanger, micro-tube heat exchanger and control unit. The experimental tests of the final system resulted in 250 N force with 2 mm displacement and 1.0 Hz actuation frequency in closed-loop operation, in which the hot and the cold fluid were re-circulated by pumps.

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42

Ismail, Basel Ismail A. "The heat transfer and the soot deposition characteristics in diesel engine exhaust gas recirculation system cooling devices /." *McMaster only, 2004.

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43

Lakhanpal, Chetan. "Mathematical modelling of applied heat transfer in temperature sensitive packaging systems. Design, development and validation of a heat transfer model using lumped system approach that predicts the performance of cold chain packaging systems under dynamically changing environmental thermal conditions." Thesis, University of Bradford, 2009. http://hdl.handle.net/10454/5776.

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Development of temperature controlled packaging (TCP) systems involves a significant lead-time and cost as a result of the large number of tests that are carried out to understand system performance in different internal and external conditions. This MPhil project aims at solving this problem through the development of a transient spreadsheet based model using lumped system approach that predicts the performance of packaging systems under a wide range of internal configurations and dynamically changing environmental thermal conditions. Experimental tests are conducted with the aim of validating the predictive model. Testing includes monitoring system temperature in a wide range of internal configurations and external thermal environments. A good comparison is seen between experimental and model predicted results; increasing the mass of the chilled phase change material (PCM) in a system reduces the damping in product performance thereby reducing the product fluctuations or amplitude of the product performance curve. Results show that the thermal mathematical model predicts duration to failure within an accuracy of +/- 15% for all conditions considered.

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44

Duty, Chad Edward. "Design, operation, and heat and mass transfer analysis of a gas-jet laser chemical vapor deposition system." Diss., Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/17925.

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45

Schulz, Sebastian [Verfasser]. "Flow and heat transfer phenomena in a complex impingement system for integrally cooled turbine blades / Sebastian Schulz." München : Verlag Dr. Hut, 2018. http://d-nb.info/1155056094/34.

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46

Morisson, Vincent. "Heat transfer modelling within graphite/salt composites : from the pore scale equations to the energy storage system." Bordeaux 1, 2008. http://www.theses.fr/2008BOR13581.

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Ce travail de thèse s'inscrit dans le cadre du projet européen DISTOR dont le but est de concevoir des systèmes de stockage d'énergie adaptés aux centrales solaires utilisant la technologie DSG (génération de vapeur direct). Les matériaux à changement de phase élaborés sur la base d'une matrice de graphite dont les pores sont remplis de sel, ont été identifiés comme étant les meilleurs candidats tant en terme de stockage, qu'en terme de coût et d'adaptation aux paramètres de fonctionnement de notre centrale solaire. L'objectif de ce travail a été d'étudier le comportement thermique de ce matériau composite à 3 échelles ; à l'échelle du pore, de l'échantillon et du système de stockage. Il a pu ainsi être démontré que les transferts thermiques au sein d'un matériau graphique/sel peuvent être représentés à l'échelle macroscopique par l'intermédiaire d'un modèle Enthalpie Température standard avec des propriétés thermiques équivalentes et des fonctions enthalpie température correspondant à une fusion étalée plutôt que localisée. Une méthode permettant la caractérisation complète des composites Graphite/Sel a été proposée à travers un seul échantillon et une seule expérience. Enfin un outil pour la conception préliminaire et l'analyse du système de stockage a été développé. Les avantages d'utiliser les MCP développés dans le cadre du projet DISTOR ont ainsi pu être mis en avant.

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47

Kendrick, Clint Edward. "Development of model for large-bore engine cooling systems." Thesis, Kansas State University, 2011. http://hdl.handle.net/2097/8721.

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Master of Science
Department of Mechanical and Nuclear Engineering
Kirby S. Chapman
The purpose of this thesis is to present on the development and results of the cooling system logic tree and model developed as part of the Pipeline Research Council International, Inc (PRCI) funded project at the Kansas State National Gas Machinery Laboratory. PRCI noticed that many of the legacy engines utilized in the natural gas transmission industry were plagued by cooling system problems. As such, a need existed to better understand the heat transfer mechanisms from the combusting gases to the cooling water, and then from the cooling water to the environment. To meet this need, a logic tree was developed to provide guidance on how to balance and identify problems within the cooling system and schedule appropriate maintenance. Utilizing information taken from OEM operating guides, a cooling system model was developed to supplement the logic tree in providing further guidance and understanding of cooling system operation. The cooling system model calculates the heat loads experienced within the engine cooling system, the pressures within the system, and the temperatures exiting the cooling equipment. The cooling system engineering model was developed based upon the fluid dynamics, thermodynamics, and heat transfer experienced by the coolant within the system. The inputs of the model are familiar to the operating companies and include the characteristics of the engine and coolant piping system, coolant chemistry, and engine oil system characteristics. Included in the model are the various components that collectively comprise the engine cooling system, including the water cooling pump, aftercooler, surge tank, fin-fan units, and oil cooler. The results of the Excel-based model were then compared to available field data to determine the validity of the model. The cooling system model was then used to conduct a parametric investigation of various operating conditions including part vs. full load and engine speed, turbocharger performance, and changes in ambient conditions. The results of this parametric investigation are summarized as charts and tables that are presented as part of this thesis.

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48

Su, Yu-Hao. "Power Enhancement of Piezoelectric Technology based Power Devices by Using Heat Transfer Technology." Thesis, Cachan, Ecole normale supérieure, 2014. http://www.theses.fr/2014DENS0025/document.

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L’objectif de cette étude est d’améliorer les performances des transformateurs piézoélectriques en terme de courant de sortie et de puissance pour des applications d’alimentation DC/DC, grâce à la gestion de l’échauffement. Le courant de sortie des transformateurs piézoélectriques, et donc la puissance transmise, sont directement liés à la vitesse de vibration qui pour des valeurs élevées engendre des pertes et une forte élévation de température. Cette élévation excessive de la température a comme conséquence le changement des caractéristiques du transformateur et plus particulièrement la diminution du facteur de qualité Q. Ainsi cela entraine une limite structurelle de la puissance transmise du transformateur. Une solution pour augmenter le courant de sortie est l’utilisation d’un redresseur doubleur de courant, qui grâce à 2 inductances permet, à courant de charge donné, de diminuer la vitesse de vibration du transformateur, mais ne permet pas de régler le problème d’échauffement du transformateur. Dans cette thèse nous proposons des moyens d’évacuation de la chaleur ainsi que le choix de l’environnement dans lequel le transformateur devra fonctionner. L’influence de différents systèmes de refroidissement d’un convertisseur DC/DC à base transformateur piézoélectrique est étudiée. L’étude thermique du transformateur piézoélectrique multicouche polarisé en épaisseur et ayant des électrodes circulaires met en évidence un comportement non linéaire. Une plaque vibrante piézoélectrique est d’abord envisagée pour créer un flux d’air qui augmente l’évacuation de chaleur par convection, puis un module de refroidissement utilisant l’effet thermoélectrique. Les mesures montrent que la première solution est plus avantageuse car elle améliore sensiblement les performances du transformateur pour un coût énergétique très faible. Une étude thermique par éléments finis complète cette étude, montrant que l’approche par schéma électrique est pertinente. La puissance que peut délivrer le transformateur sur une charge optimale est encore augmentée. Enfin, ce travail montre qu’en combinant les dispositifs de refroidissement tout en respectant la condition de température inférieure à 55°C, le rendement du convertisseur reste raisonnable (70%) et la puissance disponible peut doubler dans le meilleur des cas
The objective of this study was to increase the output current and power in a piezoelectric transformer (PT) based DC/DC converter by adding a cooling system. It is known that the output current of PT is limited by temperature build-up because of losses especially when driving at high vibration velocity. Excessive temperature rise will decrease the quality factor Q of piezoelectric component during the operational process. Simultaneously the vibration energy cannot be increased even if under higher excitation voltage. Although connecting different inductive circuits at the PT secondary terminal can increase the output current, the root cause of temperature build-up problem is not solved.This dissertation presents the heat transfer technology to deal with the temperature build-up problem. With the heat transfer technology, the threshold vibration velocity of PT can be increased and thus the output current and output power (almost three times).Furthermore, a comparison between heat transfer technology and current-doubler rectifier applied to the piezoelectric transformer based DC/DC converter was also studied. The advantages and disadvantages of the proposed technique were investigated. A theoretical-phenomenological model was developed to explain the relationship between the losses and the temperature rise. It will be shown that the vibration velocity as well as the heat generation increases the losses. In our design, the maximum output current capacity can increase 100% when the operating condition of PT temperature is kept below 55°C. The study comprises of a theoretical part and experimental proof-of-concept demonstration of the proposed design method

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49

Niedermeier, Klarissa [Verfasser], and T. [Akademischer Betreuer] Wetzel. "Numerical investigation of a thermal storage system using sodium as heat transfer fluid / Klarissa Niedermeier ; Betreuer: T. Wetzel." Karlsruhe : KIT Scientific Publishing, 2019. http://d-nb.info/1196294720/34.

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50

Nordlander, Erik. "Modelling and Validation of a Truck Cooling System." Thesis, Linköping University, Department of Electrical Engineering, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-12220.

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In the future, new challenges will occur during the product development in the vehicular industry when emission legislations getting tighter. This will also affect the truck cooling system and therefore increase needs for analysing the system at different levels of the product development. Volvo 3P wishes for these reasons to examine the possibility to use AMESim as a future 1D analysis tool. This tool can be used as a complement to existing analysis methods at Volvo 3P. It should be possible to simulate pressure, flow and heat transfer both steady state and transient.

In this thesis work a cooling system of a FH31 MD13 520hp truck with an engine driven coolant pump is studied. Further a model of the cooling system is built in AMESim together with necessary auxiliary system such as oil circuits. The model is validated using experimental data that have been produced by Volvo 3P at the Gothenburg facility.

The results from validation and other simulations show that the model gives a good picture of the cooling system. It also gives information about pressure, flow and heat transfer in steady state conditions. Further a design modification is done, showing how a change affects the flow in the cooling system.

The conclusion is that a truck cooling system can be built and simulated in AMESim. Further, it shows that AMESim meets the requirements Volvo 3P in Gothenburg has set up for the future 1D analysis tool and thereby AMESim is a good complement to the already existing analysis method.

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