Dissertations / Theses on the topic 'Cross-flow heat exchangers'
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Li, Ming. "An experimental and theoretical study of fluidelastic instability in cross flow multi-span heat exchanger tube arrays /." *McMaster only, 1997.
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Tough, M. C. "A heat transfer model of forced convection, cross flow heat exchangers used in space heating." Thesis, Cardiff University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.259171.
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Halim, Mohammed Salim. "Detailed velocity measurements of flow through staggered and in-line tube banks in cross-flow using laser doppler anemometry." Thesis, University of Manchester, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.235574.
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Cole, Brian D. "Transient performance of parallel-flow and cross-flow direct transfer type heat exchangers with a step temperature change on the minimum capacity rate fluid stream. /." Online version of thesis, 1995. http://hdl.handle.net/1850/11924.
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Ingold, Abram M. "Single-pass cross-flow micro-channel heat exchangers for use in organic Rankine cycles /." Available to subscribers only, 2007. http://proquest.umi.com/pqdweb?did=1402175291&sid=9&Fmt=2&clientId=1509&RQT=309&VName=PQD.
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Wipplinger, Karl Paul Martin. "Utilising a high pressure, cross flow, stainless steel fintube heat exchanger for direct steam generation from recovered waste heat." Thesis, Stellenbosch : Stellenbosch University, 2004. http://hdl.handle.net/10019.1/50217.
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Thesis (MScEng) -- Stellenbosch University, 2004.ENGLISH ABSTRACT: Around the world the implementation of heat recovery systems is playing an increasingly important role in the engineering inqustry. The recovered energy is utilised in the plants and saves companies millions in expenses per year. Not only is this seen on the grand scale of industry, but also in everyday life, where for instance turbochargers are used to boost the performance of automobiles by utilising the wasted energy expelled along with exhaust gasses. The aim of this project is to investigate a small scale waste heat recovery system, and to determine the optimum method by which to convert the recovered energy into electrical energy, which can be used as a secondary energy source. The research contained in this thesis, centres on the main components and theory needed for the construction of a small scale waste heat recovery system. Also included, is a theoretical analysis concerning the design and construction of the system, utilising researched theory and a simulation program of the recovery system. The simulation is control volume-based and generates property data on the fluid and exhaust gas throughout the heat exchanger. The final design included a finite element stress analysis of certain parts of the system to ensure safe testing at high pressures and temperatures. The final design resulted in a high pressure, cross flow, stainless steel fintube heat exchanger that, by using a continuous combustion unit as energy source and water as the working fluid, reached efficiencies of up to 74% in direct steam generation testing. The tube-side of the heat exchanger was designed to withstand pressures of up to 2MPa (20bar), which is imperative for the implementation of the next phase, where a turbocharger will be connected to the heat exchanger. The completion of this part of the project has paved the way for further development and implementation of the heat recovery system.
AFRIKAANSE OPSOMMING: Die herwinning van energie begin 'n toenemend belangrike rol in die ingenieurs industrie speel. Die herwonne energie word in fabrieke ben ut en spaar maatskappye milj oene aan uitgawes per jaar. Hierdie beginsel word nie net in die grootskaalse nywerhede toegepas nie, maar ook in die allerdaagse lewe, soos byvoorbeeld in voertuie waar turbo-aanjaers gebruik word om die energie-uitset van enjins te verhoog deur bloot gebruik te maak van die verlore energie wat saam met die uitlaatgasse in die atmosfeer gepomp word. Die doel van hierdie projek is om 'n kleinskaalse energieherwinningstelsel te ondersoek en die mees effektiewe metode te vind om die herwinde energie na elektriese energie om te skakel wat as 'n sekondere energiebron gebruik kan word. Die navorsing bevat in die tesis, kyk na al die hoofkomponente en teoretiese kennis wat nodig is vir die konstruksie van 'n kleinskaalse hitteherwinningstelsel. Ook ingesluit is 'n teoretiese analise ten opsigte van die ontwerp en konstruksie van die sisteem. Dit behels die gebruik van nagevorsde teorie saam met 'n simulasie program van die herwinnings stelsel. Die simulasie program is op kontrole volumes gebasseet en genereer uitlaatgas- en water eienskappe soos dit deur die hitteruiler vloei. Die finale ontwerp bevat 'n eindige element spannmgs analise van sekere kritiese komponente in die stelsel om die veilige gebruik van die sisteem by hoe drukke en temperature te verseker. Die finale ontwerp was 'n hoedruk, kruisvloei, vlekvrye staal finbuis hitteruiler. Deur 'n konstante verbrandingseenheid as energiebron te gebruik saam met water as werksvloeier, het die hitteruiler effektiwiteite van tot 74% in direkte stoomgenerasie-toetse bereik. Die hitteruiler is ontwerp om hoe drukke van tot 2MPa (20bar) te hanteer wat baie belangrik is vir die implementasie van die volgende fase van die projek waar 'n turbo-aanjaer aan die stelsel gekoppel sal. Die suksesvolle voltooiing van hierdie fase van die projek het die weg gebaan vir die verdere ontwikkeling en implimentasie van die energieherwinningsstelsel.
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Otava, Jiří. "Návrh vzduchotechnického zařízení s ohledem na systém zpětného získávání tepla." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2017. http://www.nusl.cz/ntk/nusl-265724.
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This diploma thesis is focused on problems of heat exchangers. There are two main objectives. The first objective is based on long-term measuring of enthalpy heat exchanger, processing of measured data and comparison of result with manufacturer's results. The second objective is design of variant solutions for two types of heat exchanger of air conditioning unit of selected shop. For variant without moisture transportation was selected cross flow exchangers. Thanks to knowledge from long-term measurement, was selected enthalpy heat exchanger for variant with moisture transportation. Chosen variants were compared with emphasis on heat and moisture exchange efficiency with requirements on Ecodesign.
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Ng, Eton Yat-Tuen, and eton_ng@hotmail com. "Vehicle engine cooling systems: assessment and improvement of wind-tunnel based evaluation methods." RMIT University. Aerospace, Mechanical and Manufacturing Engineering, 2002. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20080422.100014.
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The high complexity of vehicle front-end design, arising from considerations of aerodynamics, safety and styling, causes the airflow velocity profile at the radiator face to be highly distorted, leading to potentially reduced airflow volume for heat dissipation. A flow visualisation study showed that the bumper bar significantly influenced the cooling airflow, leading to three-dimensional vortices in its wake and generating an area of relatively low velocity across at least one third of the radiator core. Since repeatability and accuracy of on-road testing are prejudiced by weather conditions, wind-tunnel testing is often preferred to solve cooling airflow problems. However, there are constraints that limit the accuracy of reproducing on-road cooling performance from wind-tunnel simulations. These constraints included inability to simulate atmospheric conditions, limited tunnel test section sizes (blockage effects) and lack of ground effect simulations. The work presented in this thesis involved use of on-road and wind-tunnel tests to investigate the effects of most common constraints present in wind tunnels on accuracy of the simulations of engine cooling performance and radiator airflow profiles. To aid this investigation, an experimental technique for quantifying radiator airflow velocity distribution and an analytical model for predicting the heat dissipation rate of a radiator were developed. A four-hole dynamic pressure probe (TFI Cobra probe) was also used to document flow fields in proximity to a section of radiator core in a wind tunnel in order to investigate the effect of airflow maldistribution on radiator heat-transfer performance. In order to cope with the inability to simulate ambient temperature, the technique of Specific Dissipation (SD) was used, which had previously been shown to overcome this problem.
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Aliev, Ruslan. "CFD Investigation of Heat Exchangers with Circular and Elliptic Cross-Sectional Channels." Cleveland State University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=csu1452678890.
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Albrecht, Daniel David. "DESIGN AND CONSTRUCTION OF HEAT EXCHANGER TEST STAND WITH INITIAL TEST RESULTS." OpenSIUC, 2009. https://opensiuc.lib.siu.edu/theses/109.
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Continual development of internal combustion engines requires greater performance from liquid coolants and heat exchangers to maintain optimal temperature. For the purpose of experimental testing of traditional, compact, and microchannel heat exchangers, a test facility has been designed, constructed, and utilized. The facility includes equipment and instrumentation necessary to create operating conditions and record data primarily for testing plate-fin brazed aluminum heat exchanger where heat is being transferred from liquid to air. Other arrangements of heat exchangers could be tested as well with some modifications. Initial tests were performed at several specified operating conditions for three liquids: water, a traditional glycol based Extended Life Coolant (ELC), and a new Glycol Free Coolant (GFC) in an attempt to characterize their heat transfer ability. Results of the tests found that the product of overall heat transfer coefficient and heat exchanger area (UA) was very similar for GFC and water, and it was less for ELC by a narrow margin of 1.3% difference on average. Uncertainty due to instrumentation accuracy was calculated to be 1.8% on average making the results overall UA unverifiable. Measured pressure drop across the heat exchanger which is proportional to required pumping power was found to be 13.5% higher for GFC than ELC at nominal conditions. The GFC offers similar heat transfer performance and marginally increased pumping power requirements compared to the traditional ELC. Due to similar heat transfer performance and the small effect of pressure drop, GFC would be good alternative to ELC due to its less toxic composition.
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Stratman, Jason Becker Bryan R. "Performance prediction of an air dehumidifying non-metallic plate cross flow heat exchanger." Diss., UMK access, 2005.
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Thesis (M.S.)--School of Computing and Engineering. University of Missouri--Kansas City, 2005."A thesis in mechanical engineering." Typescript. Advisor: Bryan R. Becker. Vita. Title from "catalog record" of the print edition Description based on contents viewed June 26, 2006. Includes bibliographical references (leaves 57-59). Online version of the print edition.
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Lind, Eric K. "Analysis of turbulence models in a cross flow pin fin micro-heat exchanger." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2002. http://library.nps.navy.mil/uhtbin/hyperion-image/02Jun%5FLind.pdf.
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Truster, Nicholas Leigh. "A REDUCED-ORDER COMPUTATIONAL MODEL OF A TWO-PASS, CROSS-FLOW CONFORMAL HEAT EXCHANGER FOR AEROSPACE APPLICATIONS." Miami University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=miami1480535587051259.
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Li, Ming. "An experimental and theoretical study of fluidelastic instability in cross flow multi-span heat exchanger tube arrays." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0004/NQ42748.pdf.
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Kuráňová, Helena. "Výměníky tepla." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2019. http://www.nusl.cz/ntk/nusl-392077.
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The master thesis deals with the issue of heat recovery and efficiency of exchangers. The experimental part is dedicated to the measurment of efficiency of a plastic model of heat exchanger with atypical construction compared to a standard plate heat exchanger. For production of the heat exchangers 3D printer was used so the thesis uses the possibilities that 3D printing is offering nowadays.
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Bartošek, Nikola. "Analýza potíží výměníku tepla." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2015. http://www.nusl.cz/ntk/nusl-232124.
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The master thesis is focused on analysis of specific cross-flow in-line tube bundle heat exchanger which deals with significant operational problems. Thermal, hydraulic and vibration calculation analysis of selected parts of the heat exchanger is performed based on CFD flow distribution results. Calculation is performed by using Maple software. Thermal and hydraulic calculations are compared with results obtained by commercial software HTRI.
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Housírek, Jiří. "Výpočtové postupy příčně obtékaného svazku trubek." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2012. http://www.nusl.cz/ntk/nusl-230361.
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This diploma thesis deals with calculation methods of heat exchanger with cross-flow tube bundle. The first part of the thesis contains summary of generally known basic calculation relations used in calculations of heat exchangers and a detailed description of a given heat exchanger.The second part of the thesis provides a description of available calculation methods of a given aparatus required for its thermal and hydraulic calculation. The final part describes application POST in 1.0 which has been formed on the basis of these calculation methods. Using this application check calculation of exchanger with cross-flow tube bundle was carried out and gained figures compared with results gained by means of professional calculation program HTRI.
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Jonák, Martin. "Návrh výměníků tepla pro vysokoteplotní aplikace." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2010. http://www.nusl.cz/ntk/nusl-229334.
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This thesis is devoted to thermal-hydraulic design and rating of heat exchangers with the specialized commercial software HTRI. These heat exchangers are solved for real high-temperature applications, where the hot fluid is a flue gas with high temperature (above 500 °C). In the thesis is made a brief analysis of the conventional design of heat exchangers usable for high-temperature aplications, description of the basic relations, description and brief user manual of software HTRI. Further, work includes a comparative study of methods for calculation of pressure drop of the fluid at 180° elbows, as support analysis for solution of required applications characterized by low pressure drop of process fluids.
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Alotaibi, Sorour Abdulhadi. "Temperature controllability in cross-flow heat exchangers and long ducts." 2003. http://etd.nd.edu/ETD-db/theses/available/etd-07082003-091400/.
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Thesis (Ph. D.)--University of Notre Dame, 2003.Thesis directed by Mihir Sen for the Department of Aerospace and Mechanical Engineering. "June 2003." Includes bibliographical references (leaves 139-143).
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Chan, Shu-Po, and 詹舒博. "Influence of Core Flow and Boundary Layer Flow Induced by Perturbator and Channel Cross-Sectional Geometry on Heat Transfer Performance in Heat Exchangers." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/h28q2j.
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博士國立清華大學
動力機械工程學系
106
This work attempts to enlighten the influence of core flow disturbance and boundary layer disturbance on momentum and energy transport. Local temperature distributions over entire heated surfaces with the associated pressure drops are examined using Infrared Thermometry (IT) and pressure transducers with Reynolds number (Re) ranging from 5,000 to 20,000. The detailed turbulent flow features are measured with Particle Image velocimetry (PIV) to provide the flow physics attributed to the heat transfer performances at a fixed Re of 10,000. The first part of the present study explores the detailed flow fields, heat transfer distributions, and pressure drop penalties in a stationary two-pass smooth parallelogram channel with 180-deg sharp bend as the baseline case. The particular asymmetrically and suddenly contracted inlet condition (hereinafter referred to as “ASI”) emulates the abrupt flow entrance of the real gas turbine blade cooling conditions. The secondary-flow patterns as well as the near-wall streamwise mean velocity components and turbulent kinetic energy are analyzed to correlate the relationship between flow characteristics and heat transfer distributions. The most distinct finding of this study is the asymmetric thermal and fluid flow features on the top and bottom wall side, in contrast to the symmetric ones in the corresponding square and rectangular channels. Compared with the previous fully developed inlet condition (hereinafter referred to as “FDI”) case, it is found that the thermal performance factors (TPF) of the ASI case are respectively 43.5% and 53.7% higher than those of the FDI case at Re=5,000 and 20,000 because of the entrance-induced secondary flow and disturbance. The correlations of Nu and fanning friction factor (f) are obtained to compare with those generated from the corresponding square channels. The second part of the present study explores the detailed flow patterns and turbulence parameters, including streamwise and spanwise mean flow field, secondary-flow mean velocity map, turbulent intensity, Reynolds stress and turbulent kinetic energy as well as the heat transfer performances for the two-pass ribbed parallelogram channels with three different rib orientations (45-deg, -45-deg, and 90-deg). It is found that the combined effect of inlet condition and rib orientation extends to the entire parallelogram channel rather than the first passage only. Among the rib orientations investigated, the 45-deg ribs enhance the effects of parallelogram slant sidewalls and entrance to extend the Nu differences between the top and bottom walls. In contrast, the other two rib configurations, 90-deg ribs especially, weaken these effects and narrow the corresponding differences. Based on the ability to elevate the surface-averaged Nu/Nu∞ ratios, the respective orders of (45-deg, −45-deg, 90-deg) and (90-deg, 45-deg, −45-deg) for the present top and bottom walls are significantly different from those in square and rectangular channels. The variations of channel-averaged Nu/Nu∞ and f/f∞ with the associated TPF values against Re are compared with the previous results obtained from literature. In general, the three tested angled ribs all provide the TPF values above than unity. Only the TPF values in 45-deg case are always higher than those in corresponding smooth parallelogram channel (ASI case). Divided by the TPF values in ASI case, the normalized TPF values are respectively 1.09-1.04, 1.07-0.87, and 0.83-0.99 for 45, 90, −45-deg ribbed cases. It is thus important to take the entrance effect into account when applying the angled ribs in a two-pass parallelogram channel. The third part of the present study aims to propose innovative louver-type turbulators to enhance the heat transfer rate via three flow mechanics, namely core flow disturbance, jet impingement, and extended heat transfer surface. These louvers are installed in the twin-pass square channel with a fully developed inlet condition. The parameters are examined to disclose optimal design in terms of the pitch ratio (Pi/DH=1, 2, 3, 4, and ∞) and the number of slat per half louver (1≤Ns≤4). The pressure drop measurements are also performed to estimate the Fanning friction factors (f) and the thermal performance factors (TPF). The results show that both (Nu) ̅/Nu∞ and f ̅/f∞ ratios rise with descending Pi/DH and ascending Ns under the present test conditions. Among all the tested cases, the case with Pi/DH=1 and Ns=4 provides the highest Nu/Nu∞, almost twice the value of smooth reference. Nevertheless, it suffers from high f/f∞ penalty. The TPF level is a relatively weak function of Pi/DH. There exists a critical slat number of Ns=3 above which the TPF value is a weak function of Ns. Below the critical Ns, the TPF value increases with decreasing Ns. From the viewpoint of heat transfer enhancement, one could apply the louvered channel as a heat exchanger with small Pi/DH and large Ns. The boundary layer disturbance, on the other hand, is more cost-effective than core flow disturbance as a mechanism to augment heat transfer from the viewpoint of thermal performance.
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Ward, Christopher. "Design and performance of a small scale waste heat recovery unit." Thesis, 2011. http://hdl.handle.net/1957/26458.
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A microchannel heat exchanger was designed for diesel waste heat recovery and its performance was evaluated. The 21x15x8 cm unit was constructed from diffusion brazed stainless steel lamina and weighed 11 kg. Operating from a 13.4 kW generator with an exhaust temperature of 500 °C the unit delivered 11.1 kW of thermal energy at the design point with an effectiveness of 0.87. If coupled with an organic Rankine bottoming cycle this has the potential of boosting system power output by 35%. Performance was found to be insensitive to cold side flow conditions. Soot accumulation was found to be problematic, which caused a steady exhaust pressure rise at the device but did not affect the thermal performance.Graduation date: 2012
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黃文利. "An Investigation of Flow Boiling Heat Transfer on Cross-flow Microchannel Heat Exchanger with Gas Heating." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/46370273489837297924.
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碩士國立清華大學
工程與系統科學系
100
To utilize the exhausted heat produced from a methanol reformer (a part of a reformed methanol fuel cell) effectively, the development of a highly effective microchannel heat exchanger (MCHE) is of critical importance. This design could not only reduce the temperature of the hydrogen released from a reformer but also transfer the heat to the liquid methanol. Following our previous researches on the co- and counter-flow MCHEs, the two-phase flow boiling heat transfer characteristics in a cross-flow MCHE is investigated in the present work. The MCHE is made from 4-inches silicon wafer prepared through microfabrication processes with a dimension of 20 mm × 20 mm. Eighteen microchannels are etched on each side, and covered with Pyrex 7740 glass by anodic bonding. The channel depth on both cold- and hot-side is 200 μm, and the thickness of the wall between is the same of 200μm. To make the boiling flow more stable, the microchannels in the cold side employ a diverging design, as suggested in our previous studies. Liquid methanol is used as the boiling fluid, while hot helium gas is employed to simulate hydrogen. From the experiment results, it indicates that in the efficiency with methanol boiling in the cold side gradually increases with an increase in hot-side thermal power. Moreover, the efficiency increases significantly with an increase in the mass flux. The highest efficiency could achieve about 0.91 and the transferred cooling power is around 50 kWm-2.
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Hammock, Gary L. "Cross-Flow, Staggered-Tube Heat Exchanger Analysis for High Enthalpy Flows." 2011. http://trace.tennessee.edu/utk_gradthes/877.
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Cross flow heat exchangers are a fairly common apparatus employed throughout many industrial processes. For these types of systems, correlations have been extensively developed. However, there have been no correlations done for very high enthalpy flows as produced by Arnold Engineering Development Center’s (AEDC) H2 facility. The H2 facility uses a direct current electric arc to heat air which is then expanded through a converging-diverging nozzle to impart a supersonic velocity to the air. This high enthalpy, high temperature air must be cooled downstream by the use of a cross flow heat exchanger.
It is of interest to evaluate the actual performance of the air cooler to determine the effectiveness of possible facility upgrades. In order to characterize cooler effectiveness, a numerical model is built to calculate per-tube-row energy balances using real (temperature and pressure dependent) air and water properties and cross-flow Nusselt number calculations.
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Lin, Jing-Feng, and 林敬峰. "Numerical Analysis of Cross-flow Fin-type Heat Exchanger and Waste Heat Recovery Experiment." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/8tw598.
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碩士國立臺灣科技大學
機械工程系
106
In view of the lack of global energy depletion and the rising oil prices, how to effectively save energy and find new alternative energy sources to reduce the dependence on fossil fuels is an urgent issue to be solved. Behind the heavy use of fossil fuels, environmentally harmful pollution has also risen. The impact of the greenhouse effect in recent years is far greater than we imagined, so these issues can no longer be ignored. Among them, the greenhouse gas part is 〖CO〗_2 and 〖CH〗_4 is the largest, so if you can directly recycle and reuse 〖CH〗_4 and 〖CO〗_2, it will not only contribute to the improvement of the greenhouse effect, but also provide energy. In this study, we will introduce the design method of heat exchangers, and explore the literature on the design or application of heat exchangers, such as the difference of heat exchangers of parallel flow, reverse flow or staggered flow. There are many types of heat exchangers, but in the experiment considering the space limitation, and the purpose of the research is to recover the waste heat of the biogas engine, the heat exchanger used is much smaller than the heat exchanger used in the industry, and the heat transfer area is also considered. The finned heat exchanger is used to increase the heat transfer area and the flow pattern is a staggered flow. The experimental fluid is heat exchange between air (high temperature fluid) and pure water (cryogenic fluid), which is provided by a blower. The intake air amount and the heat gun provide a heat source (simulating the exhaust temperature of the general engine), and heat the room temperature water to the required temperature (50° C -60 ° C). In addition to the temperature considerations, the intake flow rate, the intake air temperature, and the water amount are also Factors affecting heat recovery efficiency, calculate heat recovery efficiency, provide thermal energy and recovered thermal energy ratio as the basis for calculation, and compare temperature, flow rate and thermal efficiency. The relationship between the rates, in terms of application, is intended to apply the recovered thermal energy to the production process of anaerobic fermentation, which belongs to the recycling system of biogas.
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"Study of Cross-flow Cooling Effects in a Stirling Engine Heat Exchanger." Master's thesis, 2011. http://hdl.handle.net/2286/R.I.14279.
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abstract: While much effort in Stirling engine development is placed on making the high-temperature region of the Stirling engine warmer, this research explores methods to lower the temperature of the cold region by improving heat transfer in the cooler. This paper presents heat transfer coefficients obtained for a Stirling engine heat exchanger with oscillatory flow. The effects of oscillating frequency and input heat rate on the heat transfer coefficients are evaluated and details on the design and development of the heat exchanger test apparatus are also explained. Featured results include the relationship between overall heat transfer coefficients and oscillation frequency which increase from 21.5 to 46.1 Wm-2K-1 as the oscillation frequency increases from 6.0 to 19.3 Hz. A correlation for the Nusselt number on the inside of the heat exchange tubes in oscillatory flow is presented in a concise, dimensionless form in terms of the kinetic Reynolds number as a result of a statistical analysis. The test apparatus design is proven to be successful throughout its implementation due to the usefulness of data and clear trends observed. The author is not aware of any other publicly-available research on a Stirling engine cooler to the extent presented in this paper. Therefore, the present results are analyzed on a part-by-part basis and compared to segments of other research; however, strong correlations with data from other studies are not expected. The data presented in this paper are part of a continuing effort to better understand heat transfer properties in Stirling engines as well as other oscillating flow applications.Dissertation/Thesis
M.S. Mechanical Engineering 2011
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Ball, Ian. "Evaluation of an air-to-air cross flow plate heat exchanger using a new heat recovery test facility." Thesis, 2003. http://spectrum.library.concordia.ca/2396/1/MQ90999.pdf.
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Air-to-air heat recovery is a means of energy conservation in buildings. The plate type cross flow heat exchangers is predominantly used in the HVAC industry because of their low cost, low pressure drop, and medium to high thermal effectiveness. The two main objectives of the present research are to design, fabricate and commission a new low cost innovative heat recovery test facility, and to utilize the facility to evaluate the thermal performance of cross flow plate type heat exchanger. The heat recovery test facility was designed based on two existing North American standards for testing air-to-air heat recovery devices: ASHRAE Standard 84-1991 and CSA standard C439-00. The test facility uses two independent closed loop ducts that incorporate variable frequency drives to provide precise control of airflow. Thermocouple sensors were embedded in the plate heat exchanger allowing for a determination of the bulk air temperature distribution on both the cold and hot sides of the heat exchanger at a top, middle and bottom planes. (Abstract shortened by UMI.)
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Hsu, Wen Chuang, and 許文川. "An analysis of transfer models regarding heat and water vapor exchang through a complex paper material of a flat paper cross flow total heat exchanger." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/01812333134362810613.
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碩士中國文化大學
材料科學與製造研究所
88
The total heat exchanger has been merchandised. But it is necessary to explain the phenomena of heat and mass transfer during the processes of water vapor and heat transfer by reasonable mathematical models. By that, the test factors of the develop process can be concretely standarded and based upon. The cavity complex material used in the total heat exchanger is compounded with wood fiber, man-made fiber and absorbant materials. The goal of the research is to set up a reasonable theoretical model for predicting the efficiency of the device based on the principles of heat and mass transfer.