Journal articles: 'Primary Heat Transfer System'

1

Liu, Zhe, Peng Fu, Lei Yang, Bin Guo, Lili Zhu, Weibao Li, and Jinxuan Zhou. "Conceptual design of primary heat transfer system for CFETR power extraction system." Fusion Engineering and Design 170 (September 2021): 112395. http://dx.doi.org/10.1016/j.fusengdes.2021.112395.

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Terranova, Nicholas, and Luigi Di Pace. "DEMO WCLL primary heat transfer system loops activated corrosion products assessment." Fusion Engineering and Design 170 (September 2021): 112456. http://dx.doi.org/10.1016/j.fusengdes.2021.112456.

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Zhou, Jinxuan, Lei Yang, Bin Guo, Lili Zhu, Weibao Li, Zhe Liu, Lidong Yao, and Qianglin Xu. "Concept design of primary heat transfer system for CFETR vacuum vessel." IOP Conference Series: Earth and Environmental Science 480 (April 29, 2020): 012017. http://dx.doi.org/10.1088/1755-1315/480/1/012017.

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Misra, R. S. "Methods for Improving Thermodynamic Performance of Vapour Compression Refrigeration Systems Using Nano Mixed Ecofriendly Refrigerants in Primary Circuit and Comparsion with Nano Particles Mixed Wih R718 Used in Secondary Evaporator Circuit and Ecofriendly." International Journal of Advance Research and Innovation 3, no. 2 (2015): 165–74. http://dx.doi.org/10.51976/ijari.321532.

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The use of nano particles mixed refrigerants in a primary circuit in vapour compression refrigeration systems and used of nano particles mixed with R718 in the secondary evaporator circuit was studied in detail and computational system model was developed for solving the non linear heat transfer equations of the system. The effect of brine mass flow rate on the overall evaporator heat transfer rate and first and second law performances of VCRS have been investigated. It was observed that C.O.P enhancement about 8-28 % in the nanoparticles mixed refrigerants in a primary circuit and nanoparticles mixed refrigerants in the R718 and used in a secondary circuit is from 8% to 20% with evaporator heat transfer rate increasing is double as compared without nanoparticles in the secondary circuit due to its thermo-physical properties increases in the system.

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Si, Qiang, Jianjun Wei, and Yuan Li. "Experimental study of condensation characteristics and operation strategies of induction radiant air-conditioning system." IOP Conference Series: Earth and Environmental Science 1101, no. 7 (November 1, 2022): 072001. http://dx.doi.org/10.1088/1755-1315/1101/7/072001.

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Abstract To study the operation and condensation characteristics of an induction radiant air-conditioning system as a novel system that combines induction ventilation and radiant air conditioning, the characteristics of convection and condensation of an indoor terminal device radiant induction unit were studied. The mass transfer coefficient, condensation temperature, and condensation rate were analyzed experimentally. The time required to achieve a steady state indoor thermal environment was collected. The results indicated that the primary airflow rate and temperature mainly affected the mass transfer coefficient, condensation temperature, and condensation rate. When the indoor thermal environment reached a steady state, the heat transfer performance of the radiant induction unit was mainly affected by the primary air temperature. When condensation occurred, the primary airflow rate had a greater influence on the condensation rate. The start-up and response performances of the system were better than those of a traditional radiant air-conditioning system. In the condensation condition, reasonable control strategies maintain the primary air temperature and adjust the primary air flow rate, which can ensure sufficient heat transfer and stabilize the indoor thermal environment faster.

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Singh, Paritosh. "Performance Analysis of Shell and Tube Type Heat Exchanger Using Aluminium Oxide (Al2O3) Nano-Particle." International Journal for Research in Applied Science and Engineering Technology 9, no. 9 (September 30, 2021): 157–64. http://dx.doi.org/10.22214/ijraset.2021.37944.

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Abstract: Research in convective heat transfer using suspensions of nanometer sized solid particles in a base fluid started only over the past decade. Recent investigations on nanofluids, as such suspensions are often called, indicate that the suspended nanoparticles markedly change the transport properties and heat transfer characteristics of the suspension. The very first part of the research work summarizes about the various thermo physical properties of Al2O3 Nanofluid. In evacuated tube solar water heating system nanofluids are used as primary fluid and DM water as secondary fluid in Shell and Tube Heat Exchanger. The experimental analysis of Shell and Tube heat exchanger integrated with Evacuated tube solar collector have been carried out with two types of primary fluids. Research study of shell and tube heat exchanger is focused on heat transfer enhancement by usage of nano fluids. Conventional heat transfer fluids have inherently low thermal conductivity that greatly limits the heat exchange efficiency. The result of analysis shows that average relative variation in LMTD and overall heat transfer coefficient is 24.56% and 52.0% respectively. The payback period of system is reduced by 0.4 years due to saving is in replacement cost of Evacuated Tube Collector. Keywords: ETC; Nanofluid; LMTD; Thermal Conductivity; Overall heat transfer coefficient

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Martelli, Emanuela, Fabio Giannetti, Gianfranco Caruso, Andrea Tarallo, Massimiliano Polidori, Luciana Barucca, and Alessandro Del Nevo. "Study of EU DEMO WCLL breeding blanket and primary heat transfer system integration." Fusion Engineering and Design 136 (November 2018): 828–33. http://dx.doi.org/10.1016/j.fusengdes.2018.04.016.

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Moscato, I., L. Barucca, S. Ciattaglia, P. A. Di Maio, and G. Federici. "Preliminary design of EU DEMO helium-cooled breeding blanket primary heat transfer system." Fusion Engineering and Design 136 (November 2018): 1567–71. http://dx.doi.org/10.1016/j.fusengdes.2018.05.058.

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Popov, Emilian, and Alice Ying. "Modeling and Simulation of the ITER First Wall/Blanket Primary Heat Transfer System." Fusion Science and Technology 60, no. 1 (July 2011): 128–33. http://dx.doi.org/10.13182/fst11-a12339.

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Preda, Andrei, and Andrei Alexandru Scupi. "Energy Review on a Maritime Energy Transfer System for Comercial Use." Advanced Materials Research 837 (November 2013): 763–68. http://dx.doi.org/10.4028/www.scientific.net/amr.837.763.

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Despite the low energy and lower maintenance benefits of marine heat pump systems, little work has been undertaken in detailed analysis and simulation of such systems. This heat pump system is very attracting increasing research interests, since the system can be powered by thermal energy that can be provided by a renewable source: the difference of temperature between the ocean water layers.This paper focuses on the annual energy consumption and COP ( performance coefficent) of a marine heat pump system implemented for comercial use. This unconventional maritime systems of energy transfer would solve some of the pollution problems that arise from the use of conventional fuels . By using this system can make a pretty big energy savings in heating our homes and in preparation of hot water for domestic use.This energy consumption takes into account the heating and cooling needs of structure along different periods of time, such as winter and summer. Moreover, for each year period, we compared the heat pump efficiency simulated for our cost line with other tree tipes of heat pumps that are using diffrents primary agents. To highlight the performance of heat pump used for this study we coupled it with solar panels. The simulation, performed with TRNSYS (Transient Systems Simulation Program), was made for different working conditions simulating real conditions and temperature variations that occur in a year in the Black Sea coastal area.This experiment is intended to emphasize that marine energy potential that we have and also the advantages of using unconventional energy in relation to the use of classic fuels.This unconventional system of thermal energy conversion can be applied to both residential and commercial areas bringing an important benefit both people and the environment.

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Gu, Ya Xiu, Tian Wang, Wei Liu, and Feng Feng Ma. "Energy-Saving Analysis and Heat Transfer Performance of Wastewater Source Heat Pump." Applied Mechanics and Materials 694 (November 2014): 211–17. http://dx.doi.org/10.4028/www.scientific.net/amm.694.211.

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There is a large potential in the heat loss from the urban wastewater. In all kinds of low-grade heat sources, urban wastewater is gradually widely used because of its advantages such as huge quantities, small variation of temperature, warm in winter and cool in summer, etc. By integrating a heat pump to utilize this heat, the wastewater source heat pump (WWSHP), which is a new water reuse and treatment strategy to tackle the water problems of China and to realize the sustainable development, recovers the heat of wastewater. The WWSHP air conditioning system as residential application can reduce the need of energy systems based on fossil fuel for cooling, heating, and hot water's supply purposes. The system's working principle, classification and the wastewater's characteristic parameters were discussed in this paper. And the scheme of using WWSHP system for central air-conditioning compared with other refrigerating and heating equipments was analyzed in detail. The investigation into COP (Coefficient of Performance) and PER (Primary Energy Ratio) was shown in this paper. Among the four kinds of common air conditioning units, when the loads are same respectively, the WWSHP has the most significant energy-saving effect. Furthermore, mechanism of heat transfer enhancement for falling-film evaporation and condensation surface of tubes packed with wire-mesh is also studied in detail. Theoretical simulation will be carried out for the heat transfer process and the flow of falling-film outside horizontal tubes. Improvement of controlling parameters influenced the evaporation and condensation performance, and then led to an increase in the refrigerating quantity and the COP. Consequently, this WWSHP system has its theoretical significance and promising engineering application potentials for the residential refrigerating and air-conditioning system using low-temperature waste heat source.

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Życzyńska, Anna, Zbigniew Suchorab, Dariusz Majerek, and Violeta Motuzienė. "Statistical Analysis of the Variability of Energy Efficiency Indicators for a Multi-Family Residential Building." Energies 15, no. 14 (July 11, 2022): 5042. http://dx.doi.org/10.3390/en15145042.

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During the building design phase, a lot of attention is paid to the thermal properties of the external envelopes. New regulations are introduced to improve energy efficiency of a building and impose a reduction of the overall heat transfer coefficient; meanwhile, this efficiency is more influenced by the efficiency of the heating system and the type of fuels used. This article presents a complex analysis including the impact of: heat transfer coefficient of the envelope, efficiency of building service systems, the type of energy source, and the fuel. The analysis was based on the results of simulation tests obtained for an exemplary multi-family residential building located in Poland that is not equipped with a cooling system. The conducted calculations gave quantitative evaluation of the influence of particular parameters on building energy performance and showed that the decrease of heat transfer coefficient of building boundaries, in accordance to the Polish regulation for 2017 and 2021, gave only 11% of reduction on usable energy demand index. On the other hand, it was found that modification of the heating system and heat source can significantly influence the values of the final and primary energy consumption at the level of 70%. The application of heat pumps has a greater influence on the final and primary energy consumption for heating indices than other parameters, such as the building’s envelopes.

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Skosana, P. J., D. S. van Vuuren, and M. D. Heydenrych. "Wall Heat Transfer Coefficient in a Molten Salt Bubble Column: Testing the Experimental Setup." Advanced Materials Research 1019 (October 2014): 195–203. http://dx.doi.org/10.4028/www.scientific.net/amr.1019.195.

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One of the advantages of bubble columns is high heat transfer rates. High heat transfer is important in reactors when high thermal duties are required. An appropriate measurement of heat transfer coefficient is of primary importance for designing reactors that are highly exothermic or endothermic. This paper presents the design and operation of experimental setup used for measurement of the heat transfer coefficient in molten salt media. The experimental setup was operated with tap water, heat transfer oil 32, LiCl–KCl eutectic and argon gas. Tap water was operated at the temperature of 40oC and heat transfer oil was operated at the temperature of 75oC, 103oC and 170oC. There were some challenges when operating the bubble column with molten salt due to leakages on the welds and aggressive corrosion on the column. All the experiments were run at superficial gas velocities of 0.01–0.05 m/s. Three heating tapes, each connected to a corresponding variable AC voltage controller, were used to heat the column media. Heat transfer coefficients were measured by inducing a known heat flux through the column wall and measurement of the temperature difference between the wall and the contents. In order to balance the system, heat was removed by the cooling water flowing through a copper tube on the inside of the column. Temperature differences between the column wall and the liquid were measured at five axial locations. It was found that the heat transfer coefficient increases with superficial gas velocity. The values of heat transfer coefficient for argon–water system were higher than those of argon–heat transfer oil system. Heat transfer coefficient was also found to increase with an increase in temperature.

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Carbajo, Juan, Graydon Yoder, G. Dell’Orco, Warren Curd, and Seokho Kim. "Modeling and analysis of alternative concept of ITER vacuum vessel primary heat transfer system." Fusion Engineering and Design 85, no. 10-12 (December 2010): 1852–58. http://dx.doi.org/10.1016/j.fusengdes.2010.06.010.

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Lin, Shuang, Xiaoman Cheng, Kai Huang, and Songlin Liu. "Preliminary design of primary heat transfer system for CFETR Water-Cooled Ceramic Breeder blanket." Fusion Engineering and Design 140 (March 2019): 27–32. http://dx.doi.org/10.1016/j.fusengdes.2019.01.132.

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VELMURUGAN, Sankaralingam, Sasikumar PADMA, Sevilimedu Veeravalli NARASIMHAN, Pratap Kumar MATHUR, and P. Narasimha MOORTHY. "The Passivation Effects of Magnesium Ion on PHWR Primary Heat Transfer System Structural Materials." Journal of Nuclear Science and Technology 33, no. 8 (August 1996): 641–49. http://dx.doi.org/10.1080/18811248.1996.9731971.

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Daller, Sarah, Wolfgang Friess, and Rudolf Schroeder. "Energy Transfer in Vials Nested in a Rack System During Lyophilization." Pharmaceutics 12, no. 1 (January 11, 2020): 61. http://dx.doi.org/10.3390/pharmaceutics12010061.

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Small batch sizes are a consequence of more personalized medicine and reflect a trend in the biopharmaceutical industry. Freeze drying of vials nested in a rack system is a tool used in new flexible pilot scale processing lines. Understanding of heat transfer mechanisms in the rack loaded with vials not in direct contact with each other is necessary to ensure high quality. Lyophilization in the rack vial system enables a homogeneous drying with a reduced edge-vial-effect and shielding against radiation from surrounding components, e.g., the chamber wall. Due to the separation effect of the rack, direct shelf contact contributes approx. 40% to the overall energy transfer to the product during primary drying. Hence overall the rack is a flexible, robust tool for small batch production, which ensures a controlled heat transfer resulting in a uniform product.

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Noro, Marco, Simone Mancin, and Francesco Cerboni. "High Efficiency Hybrid Radiant and Heat Pump Heating Plants for Industrial Buildings: An Energy Analysis." International Journal of Heat and Technology 40, no. 4 (August 31, 2022): 863–70. http://dx.doi.org/10.18280/ijht.400401.

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A hybrid condensing radiant tubes system coupled to a heat pump to heat a typical industrial building was modeled in three climatic zones of Italy using dynamic simulation software. The heating system was set up by radiant tubes and an air heating system with terminals placed in the building supplied by hot water produced by the condensation of the exhausted of the radiant tubes and by a heat pump with external air heat source. An optimization of the main parameters (nominal power of the heat pump, bivalent temperature in alternative bivalent operation, and peak power of the photovoltaic system) was carried out on the basis of energy performance of the hybrid heating system. The optimal configuration of the hybrid heating system that minimizes the annual amount of total non-renewable primary energy and maximizes the non-renewable primary energy ratio was compared with traditional heating systems for industrial buildings. The energy savings of this innovative solution vary in the range of 40%-80% depending on the climate and the configuration of the system.

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Mane, Shreya. "Theoretical Aspects on Heat Transfer and Fluid Flow in Micro Channels." 3 1, no. 3 (December 1, 2022): 16–21. http://dx.doi.org/10.46632/jame/1/3/3.

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The past ten years have seen a lot of research on the issues of heat transfer and fluid flow in micro-channels. With an emphasis on upcoming research requirements, a critical analysis of the state of research as it stands is offered. Following a brief introduction, the study discusses six themes related to transport phenomena in micro-channels: condensation, cooling of electronics, single-phase gas flow, augmentation of single-phase liquid flow and flow boiling, and micro-scale heat exchangers. In this study, we investigate the three-dimensional heat transfer and water flow properties in a set of rectangular micro-channel heat sinks for advanced electronic systems. Over the past ten years, mini/micro channel type compact heat exchangers have received a lot of attention. The ability to make heat exchangers smaller, lighter, and cheaper than those in use now is the primary motivator. Additionally, emerging applications that call for the cooling of small things, such electronics and micro-electro-mechanical devices, need for heat exchangers with tiny channels. Theoretically, it is examined how a nanofluid moves and transfers heat through a horizontal micro channel while being affected by a magnetic field and an electric double layer (EDL). The flow problem for a micro channel with a large aspect ratio is handled as a two-dimensional nonlinear system. The magnetic field and EDL body force are taken into account while calculating momentum equation

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Nguyen, V. T., and H. T. Trinh. "Assessment of steam condensation model with the presence of non-condensable gas in a vertical tube using RELAP5 Mod 3.2 code and MIT exp. Data." Nuclear Science and Technology 4, no. 3 (September 30, 2014): 7–18. http://dx.doi.org/10.53747/jnst.v4i3.231.

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The non-condensable gas effect is a primary concern in some passive systems used in advanced design concepts, such as the Passive Residual Heat Removal System (PRHRS) of AP1000, APR1400, AES-2006, the Passive Containment Cooling System (PCCS) of AP1000 design, and Isolation Condensation System (ICS) of ESBWR design. The accumulation of the non-condensable gas inside the condensing tubes can significantly reduce the level of heat transfer which affects the heat removal capacity in accident condition and impacts plant safety. The objective of the present work is to assess the analysis capability of two wall film condensation models of RELAP5/Mod3.2 with the presence of non-condensable gas in a vertical tube on condensation experiments performed at MIT, USA. The results of the simulations and experimental data show the similar tendencies that the heat transfer coefficients increase as the inlet steam-non condensable gas mixture flow rate increases, the inlet steam-non-condensable gas mass fraction decrease, and the inlet saturated steam temperature decrease

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Vallone, E., L. Barucca, S. Basile, S. Ciattaglia, P. A. Di Maio, G. Federici, M. Giardina, I. Moscato, A. Quartararo, and A. Tarallo. "Pre-conceptual design of EU-DEMO divertor primary heat transfer systems." Fusion Engineering and Design 169 (August 2021): 112463. http://dx.doi.org/10.1016/j.fusengdes.2021.112463.

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Mishra, R. S., and Rahul Kumar Jaiswal. "Thermal Performance Improvements of Vapour Compression Refrigeration System Using Eco Friendly Based Nanorefrigerants in Primary Circuit." International Journal of Advance Research and Innovation 3, no. 3 (2015): 98–112. http://dx.doi.org/10.51976/ijari.331513.

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Now a days nano refrigerants are being considered as a most efficient heat transfer fluids having superior heat transfer properties than conventional refrigerants in various thermal applications. Refrigerant based nano fluid termed as “Nanorefrigerant” have the great potential for improve thing first law thermal performance in terms of coefficient of performance in the refrigeration and air conditioning system. The thermo physical properties by addition of different nanoparticle mixed with eco friendly refrigerant are analyzed and their effects on the coefficient of performance (C.O.P.) have been reported in this paper. The thermal modeling have been done for the same cooling load and same geometry parameter for all nanoparticles and refrigerant combination mixture in the vapour compression refrigeration based chiller system having two concentric tube type heat exchanger as evaporator and condenser. The experimental results are indicating the thermal conductivity, dynamic viscosity and density of nanorefrigerant (different nanoparticle i.e. Cu, Al2O3,CuO and TiO2 with eco friendly refrigerant R134a,R407c and R404A) increased about 15 to 94 %, 20% and 12 to 34 % respectively compared to base refrigerant on the other hand specific heat of nanorefrigerant is slightly lower that the base refrigerant. Moreover Al2O3/R134a nanorefrigerant shows highest C.O.P. of 35%. R404A and R407 with different nanoparticle show enhancement in C.O.P. about 3 to 14 % and 3 to 12 % respectively. Therefore application of nanorefrigerant in refrigeration and air conditioning system is most required to improve the performance of the system.

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Tukimon, Mohd Faizal, Wan Nur Azrina Wan Muhammad, M. Nor Anuar Mohamad, Nurhayati Rosly, and Norasikin Mat Isa. "Thermal Analysis of Quaternary Molten Nitrate Salts Mixture for Energy Recovery System." Key Engineering Materials 796 (March 2019): 74–79. http://dx.doi.org/10.4028/www.scientific.net/kem.796.74.

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Quaternary molten salt nitrate have been used very practically as medium for energy storage or heat transfer fluid in terms of energy recovery system. Quaternary molten salt nitrate is a mixture that can transfer heat to generate energy such as electricity. Mixed alkaline molten nitrate salt can act as a heat transfer fluid due to their advantageous in terms of heat recovery system due to high specific heat capacity, low vapour pressure, low cost and wide range of temperature in its application. This studies shows about determining the new composition of quaternary molten nitrate salts from different primary salts that can possibly give a high specific heat capacity with low melting point. The mixture of quaternary molten nitrate salts was then heated inside the box furnace at 150°C for four hours and rose up the temperature to 400°C for eight hours. Through heating process, the quaternary molten nitrate alkaline was completely homogenized. The temperature was then dropped to room temperature before removing the mixture from the furnace. The specific heat capacities of each sample were determined by using Differential Scanning Calorimeter, DSC. From the result of DSC testing, Sample 6 gives the highest point of specific heat capacity and low melting point which is 0.4648 J/g°C and 97.71°C respectively. In the nut shell, Sample 6 was chosen as a good mixture with good thermal properties that has a low melting point which is below 100°C but high specific heat capacity that may be a helpful in the application energy recovery system.

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Cheng, Xiaoman, Xuebin Ma, Wenjia Wang, Lei Chen, Songlin Liu, and Youyou Xu. "Primary heat transfer system design of the WCCB blanket for multiple operation modes of CFETR." Fusion Engineering and Design 153 (April 2020): 111489. http://dx.doi.org/10.1016/j.fusengdes.2020.111489.

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Cheng, Xiaoman, Xuebin Ma, Peng Lu, Wenjia Wang, and Songlin Liu. "Thermal dynamic analyses of the primary heat transfer system for the WCCB blanket of CFETR." Fusion Engineering and Design 161 (December 2020): 112067. http://dx.doi.org/10.1016/j.fusengdes.2020.112067.

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Islam, Md Shakerul, Altab Hossain, Khalid Murshed, and Rafi Alam Chowdhury. "Experimental Analysis on Safety System of a Simulated Small Scale Pressurized Water Reactor System with Intelligent Control." MIST INTERNATIONAL JOURNAL OF SCIENCE AND TECHNOLOGY 8 (December 16, 2020): 07–13. http://dx.doi.org/10.47981/j.mijst.08(02)2020.191(07-13).

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Reactors are widely used in the nuclear power plant due to the rapid demand for electricity by reducing the greenhouse effect. However, the effectiveness of the nuclear reactor depends on an adequate safety system. Hence, temperature and heat transfer are two critical parameters for any reactor in operation for which intelligent temperature control with an integrated safety system is essential. Therefore, the present study has emphasized the development of a simulated small-scale water-based reactor with intelligent control and safety system and examined through the analysis of thermal-hydraulic parameters. Radial heat transfer of an electric rod used as fuel in the primary circuit has been analyzed by taking sensor reading in various positions of the core. The developed system is self-controlled with all possible active and passive safety systems. Consecutively, the prototype has also been designed including manual adjustment to ensure a fail-safe environment. The system is capable to operate at temperatures between 80°C and 120°C, although the design can withstand up to 200°C. The data of the experiment are taken under the pressure of 200 kPa at 120°C temperature. Results show that heat output of 2116.09 kJ has been obtained from the system against heat input of 2514.80 kJ, which gives an efficiency around 16% of the developed system.

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Błaszczuk, Artur. "Effect of flue gas recirculation on heat transfer in a supercritical circulating fluidized bed combustor." Archives of Thermodynamics 36, no. 3 (September 1, 2015): 61–83. http://dx.doi.org/10.1515/aoter-2015-0022.

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Abstract This paper focuses on assessment of the effect of flue gas recirculation (FGR) on heat transfer behavior in 1296t/h supercritical coal-fired circulating fluidized bed (CFB) combustor. The performance test in supercritical CFB combustor with capacity 966 MWth was performed with the low level of flue gas recirculation rate 6.9% into furnace chamber, for 80% unit load at the bed pressure of 7.7 kPa and the ratio of secondary air to the primary air SA/PA = 0.33. Heat transfer behavior in a supercritical CFB furnace between the active heat transfer surfaces (membrane wall and superheater) and bed material has been analyzed for Geldart B particle with Sauter mean diameters of 0.219 and 0.246 mm. Bed material used in the heat transfer experiments had particle density of 2700 kg/m3. A mechanistic heat transfer model based on cluster renewal approach was used in this work. A heat transfer analysis of CFB combustion system with detailed consideration of bed-to-wall heat transfer coefficient distributions along furnace height is investigated. Heat transfer data for FGR test were compared with the data obtained for representative conditions without recycled flue gases back to the furnace through star-up burners.

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Bakthavatchalam, Balaji, Khairul Habib, R. Saidur, Navid Aslfattahi, Syed Mohd Yahya, A. Rashedi, and Taslima Khanam. "Optimization of Thermophysical and Rheological Properties of Mxene Ionanofluids for Hybrid Solar Photovoltaic/Thermal Systems." Nanomaterials 11, no. 2 (January 27, 2021): 320. http://dx.doi.org/10.3390/nano11020320.

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Since technology progresses, the need to optimize the thermal system’s heat transfer efficiency is continuously confronted by researchers. A primary constraint in the production of heat transfer fluids needed for ultra-high performance was its intrinsic poor heat transfer properties. MXene, a novel 2D nanoparticle possessing fascinating properties has emerged recently as a potential heat dissipative solute in nanofluids. In this research, 2D MXenes (Ti3C2) are synthesized via chemical etching and blended with a binary solution containing Diethylene Glycol (DEG) and ionic liquid (IL) to formulate stable nanofluids at concentrations of 0.1, 0.2, 0.3 and 0.4 wt%. Furthermore, the effect of different temperatures on the studied liquid’s thermophysical characteristics such as thermal conductivity, density, viscosity, specific heat capacity, thermal stability and the rheological property was experimentally conducted. A computational analysis was performed to evaluate the impact of ionic liquid-based 2D MXene nanofluid (Ti3C2/DEG+IL) in hybrid photovoltaic/thermal (PV/T) systems. A 3D numerical model is developed to evaluate the thermal efficiency, electrical efficiency, heat transfer coefficient, pumping power and temperature distribution. The simulations proved that the studied working fluid in the PV/T system results in an enhancement of thermal efficiency, electrical efficiency and heat transfer coefficient by 78.5%, 18.7% and 6%, respectively.

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Bejan, A. "Heat Transfer-Based Reconstruction of the Concepts and Laws of Classical Thermodynamics." Journal of Heat Transfer 110, no. 1 (February 1, 1988): 243–49. http://dx.doi.org/10.1115/1.3250459.

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As an alternative to the mechanistic point of view expressed in Carathe´odory’s axioms, it is shown that the laws and concepts of thermodynamics are covered also by two statements made from a purely heat transfer perspective: Axiom I′—The heat transfer is the same in all zero-work processes that take a system from a given initial state to a given final state. Axiom II′—In the immediate neighborhood of every state of a system there are other states that cannot be reached from the first via a zero-work process. The primary concepts of this formulation are heat transfer, temperature, entropy, and zero-work boundary. Axiom I′ is used to define the property “energy,” and to deduce the secondary (derived) concept of “work transfer.” Axiom II′ is used to define the thermodynamic properties of “volume” and “pressure.” In this new heat transfer-based scheme, the analog of the Kelvin–Planck statement of the second law is: “∮δW < 0 is impossible” for an integral number of cycles executed by a closed system while in communication with no more than one pressure reservoir.

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Tkachenko, Stanislav, and Nataliya Stepanova. "PREPARATION OF A PAIR WITH CERTAIN THERMODYNAMIC PARAMETERS IN THE HEAT TECHNOLOGY SYSTEM." ENGINEERING, ENERGY, TRANSPORT AIC, no. 3(106) (November 29, 2019): 109–17. http://dx.doi.org/10.37128/2520-6168-2019-3-14.

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Known methods for preparing saturated steam for use in a heat engineering system are analyzed. It was established that the flow rate of cooling water was overestimated in them, since part of this water is drained into the drainage system of the power plant and contributes part of the heat of the primary superheated steam there. In the proposed method for removing steam overheating before it is fed to a specific heat exchanger, it is proposed to use condensate from the same heat exchanger, moreover, due to evaporation of a part of the condensate (estimated 10 ... 20%), the metal consumption of the condensate drainage system decreases. The heat and mass transfer processes in the closed loop “heat exchanger – condensate line – desuperheater and separation device –– steam of saturated saturated steam – heat exchanger” are analyzed, the balance equations are compiled, the degree of uncertainty of the heat transfer and hydrodynamic processes in two-phase media is analyzed. A steam preparation system has been developed for a heat-technological consumer, in which by using all the condensate obtained in the steam heat exchanger as a cooler and observing a certain distance between the lower tube sheet of the heat exchanger and the central axis of the desuperheater, the problems of condensate drainage, its efficient use and removal of steam overheating are achieved.

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Dong, Fei, Zhiming Wang, Yakang Feng, and Jie Ni. "Numerical study on flow and heat transfer performance of serpentine parallel flow channels in a high-voltage heater system." Thermal Science, no. 00 (2021): 168. http://dx.doi.org/10.2298/tsci200926168d.

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In this study, a high-voltage heater system with a size of 310 mm ? 210 mm ? 60 mm has been numerically studied and experimentally verified to explore the influence of the cavity structure on the flow and heat transfer performance. the response surface model and analysis of variance are used to determine the influence of the length of the mainstream area of the inlet (Lin), the length of the mainstream area of the outlet (Lout), the length of the parallel flow channel (Lch) and the single channel width (W) on the flow heat transfer, and ultimately find the best structural plan. The results show that the structural parameters of the parallel flow channel are significantly more important than those of the mainstream area, with the width and length of the parallel single channel being the primary and secondary structural parameters, respectively. The optimization scheme obtained by the NGSA-II algorithm can simultaneously meet the requirements of heat transfer and flow uniformity. Specifically, compared with the original model, the flow distribution uniformity coefficient (S) and the inlet/outlet pressure drop (Ptotal) decreased by 53.49 and 19.52%, respectively, while the average heat transfer coefficient increased by 28.05%.

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Cheng, Xiaoman, Shuang Lin, and Songlin Liu. "Loss of flow accident and loss of heat sink accident analyses of the WCCB primary heat transfer system for CFETR." Fusion Engineering and Design 147 (October 2019): 111247. http://dx.doi.org/10.1016/j.fusengdes.2019.111247.

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Hibler, Susanne, and Henning Gieseler. "Heat Transfer Characteristics of Current Primary Packaging Systems for Pharmaceutical Freeze-Drying." Journal of Pharmaceutical Sciences 101, no. 11 (November 2012): 4025–31. http://dx.doi.org/10.1002/jps.23293.

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Zhou, Yuanyuan, Zhen Yan, Ming Gao, Qiumin Dai, and Yanshun Yu. "Numerical Investigation of a Novel Plate-Fin Indirect Evaporative Cooling System Considering Condensation." Processes 9, no. 2 (February 11, 2021): 332. http://dx.doi.org/10.3390/pr9020332.

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An indirect evaporative cooling system combining with thermoelectric cooling technology (i.e., TIEC system) is proposed, in which a counter-flow plate-fin indirect evaporative cooler is inserted with thermoelectric cooling (i.e., TEC) modules. In hot and humid climate, condensation may occur on the dry channel surface of the cooler. For the TIEC system, with the aid of TEC technology, the surface temperature of the dry channel can be much lower than that of a traditional indirect evaporative cooler, thus, the condensation from the primary air is more likely to take place. A numerical model of this novel TIEC system is developed with specifically taking condensation from primary air into account. Detailed performance analysis of the TIEC system is carried out. Analytical results found that the condensation from primary air reduces the dew point effectiveness by up to 45.0% by weakening the sensible heat transfer but increases the coefficient of performance by up to 62.2% by increasing the latent heat transfer, under given conditions. The effects of main operating conditions, such as the electrical current I and number n of TEC modules, inlet temperature Tp,i, humidity ratio RHp and velocity Vp of the primary air, and the mass flow rate ratio x of secondary to primary air, are investigated under non-condensation and condensation states. It is shown that condensate is more easily produced under higher I, n, Tp,i, RHp, x and lower Vp.

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Liang, Lehua, Chuhao Li, Linna Wang, Xuejian Wang, Wenjie Zeng, and Run Luo. "Sensitivity analysis of heat transfer coefficient in primary system for LMSR core power control system based on Sobol’s method." Annals of Nuclear Energy 180 (January 2023): 109442. http://dx.doi.org/10.1016/j.anucene.2022.109442.

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TAGAWA, Akihiro, Masashi UEDA, Takuya YAMASHITA, Masataka NARISAWA, and Kouichi HAGA. "Development of an ISI Robot for the Fast Breeder Reactor MONJU Primary Heat Transfer System Piping." Journal of Nuclear Science and Technology 48, no. 4 (April 2011): 504–9. http://dx.doi.org/10.1080/18811248.2011.9711726.

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Moscato, I., L. Barucca, S. Ciattaglia, F. D’Aleo, P. A. Di Maio, G. Federici, and A. Tarallo. "Progress in the design development of EU DEMO helium-cooled pebble bed primary heat transfer system." Fusion Engineering and Design 146 (September 2019): 2416–20. http://dx.doi.org/10.1016/j.fusengdes.2019.04.006.

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Smoleń, Sławomir, and Hendrik Boertz. "Calculation and Optimization of Heat Transfer between the Low Exergy Heat Source and Organic Rankine Cycle Applied to Heat Recovery Systems." Key Engineering Materials 597 (December 2013): 45–50. http://dx.doi.org/10.4028/www.scientific.net/kem.597.45.

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One of the key challenges on the area of energy engineering is the system development for increasing the efficiency of primary energy conversion and use. An effective and important measure suitable for improving efficiencies of existing applications and allowing the extraction of energy from previously unsuitable sources is the Organic Rankine Cycle. Applications based on this cycle allow the use of low temperature energy sources such as waste heat from industrial applications, geothermal sources, biomass, fired power plants and micro combined heat and power systems.Working fluid selection is a major step in designing heat recovery systems based on the Organic Rankine Cycle. Within the framework of the previous original study a special tool has been elaborated in order to compare the influence of different working fluids on performance of an ORC heat recovery power plant installation. A database of a number of organic fluids has been developed. The elaborated tool should create a support by choosing an optimal working fluid for special applications and become a part of a bigger optimization procedure by different frame conditions. The main sorting criterion for the fluids is the system efficiency (resulting from the thermo-physical characteristics) and beyond that the date base contains additional information and criteria, which have to be taken into account, like environmental characteristics for safety and practical considerations.The presented work focuses on the calculation and optimization procedure related to the coupling heat source – ORC cycle. This interface is (or can be) a big source of energy but especially exergy losses. That is why the optimization of the heat transfer between the heat source and the process is (besides the ORC efficiency) of essential importance for the total system efficiency.Within the presented work the general calculation approach and some representative calculation results have been given. This procedure is a part of a complex procedure and program for Working Fluid Selection for Organic Rankine Cycle Applied to Heat Recovery Systems.

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KARTACHI, YOUNES, and ABDELLAH MECHAQRANE. "NUMERICAL SIMULATION AND PARAMETRIC STUDIES FOR EVALUATION OF BALANCED VENTILATION AND EARTH AIR EXCHANGERS SYSTEM COUPLED TO A DOMESTIC BUILDING." International Journal of Air-Conditioning and Refrigeration 21, no. 01 (March 2013): 1350002. http://dx.doi.org/10.1142/s2010132513500028.

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In this study, we analyze the impact of ventilation heat recovery with the heating and cooling potential of earth air heat exchanger in real climatic conditions in domestic buildings in the Middle Atlas region. In our case study, we calculate the primary energy used by a domestic building built as per the conventional house design parameters required by the Moroccan regulation. We use climate data for the city of Fes in Northern Moroccan. Three system configurations were considered. The first was the mechanical extract ventilation system both with and without heat recovery. The second was the mechanical extract ventilation system with earth to air heat exchanger system (EAHEX), and the third system was the mechanical balanced ventilation system coupled with EAHEX system. Primary energy use strongly influences natural resources efficiency and the environmental impacts of energy supply activities. In this study we explore the primary energy implications of the mechanical balanced ventilation system coupled with the EAHEX system in residential buildings. The results of this study shows that the use of a balanced ventilation system, with a high efficiency instead of a mechanical extract ventilation system, decreases the final and primary energy consumption. Moreover, it decreases or increases the CO2 emission depending on the primary energy sources.

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Woudstra, N., T. P. van der Stelt, and K. Hemmes. "The Thermodynamic Evaluation and Optimization of Fuel Cell Systems." Journal of Fuel Cell Science and Technology 3, no. 2 (January 4, 2006): 155–64. http://dx.doi.org/10.1115/1.2174064.

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Energy conversion today is subject to high thermodynamic losses. About 50% to 90% of the exergy of primary fuels is lost during conversion into power or heat. The fast increasing world energy demand makes a further increase of conversion efficiencies inevitable. The substantial thermodynamic losses (exergy losses of 20% to 30%) of thermal fuel conversion will limit future improvements of power plant efficiencies. Electrochemical conversion of fuel enables fuel conversion with minimum losses. Various fuel cell systems have been investigated at the Delft University of Technology during the past 20 years. It appeared that exergy analyses can be very helpful in understanding the extent and causes of thermodynamic losses in fuel cell systems. More than 50% of the losses in high temperature fuel cell (molten carbonate fuel cell and solid oxide fuel cell) systems can be caused by heat transfer. Therefore system optimization must focus on reducing the need for heat transfer as well as improving the conditions for the unavoidable heat transfer. Various options for reducing the need for heat transfer are discussed in this paper. High temperature fuel cells, eventually integrated into gas turbine processes, can replace the combustion process in future power plants. High temperature fuel cells will be necessary to obtain conversion efficiencies up to 80% in the case of large scale electricity production in the future. The introduction of fuel cells is considered to be a first step in the integration of electrochemical conversion in future energy conversion systems.

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Kang, Changwoo, Kyung-Soo Yang, and Innocent Mutabazi. "Thermal effect on large-aspect-ratio Couette–Taylor system: numerical simulations." Journal of Fluid Mechanics 771 (April 14, 2015): 57–78. http://dx.doi.org/10.1017/jfm.2015.151.

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We have performed numerical simulations of the flow in a large-aspect-ratio Couette–Taylor system with rotating inner cylinder and with a radial temperature gradient. The aspect ratio was chosen in such a way that the base state is in the conduction regime. Away from the endplates, the base flow is a superposition of an azimuthal flow induced by rotation and an axial flow (large convective cell) induced by the temperature gradient. For a fixed rotation rate of the inner cylinder in the subcritical laminar regime, the increase of the temperature difference imposed on the annulus destabilizes the convective cell to give rise to co-rotating vortices as primary instability modes and to counter-rotating vortices as secondary instability modes. The space–time properties of these vortices have been computed, together with the momentum and heat transfer coefficients. The temperature gradient enhances the momentum and heat transfer in the flow independently of its sign.

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Aacharya, Ananta, Robin Koirala, Shuvas Khanal, and Bivek Baral. "Comparative analysis of radiant and radiator heating system for a residential building." IOP Conference Series: Materials Science and Engineering 1279, no. 1 (March 1, 2023): 012001. http://dx.doi.org/10.1088/1757-899x/1279/1/012001.

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Abstract Energy use for heating and cooling at the household level is rising annually. The residential sector consumes about 69% of energy consumption, out of which the highest percentage is shared by traditional fuel for cooking applications, followed by heating and cooling applications. In such a scenario, the primary goal should be to meet future heating and cooling energy demand through the use of novel technologies such as radiant heating systems (RHS). By utilizing low-temperature fluid flowing through the pipe, the RHS is more efficient than a standard heating system in maintaining the correct interior temperature. These systems are not frequently implemented in Nepal. It is crucial to compare the applicability of the system with technologies like radiator systems. The building provided by Urban Development and Building Construction (UDMC) is used for the study. The radiant and radiator heating system is designed, and the effects of different parameters on the heat transfer coefficient are studied. The maximum heating load is 50kWh for mid of January. A radiant heating system with a panel area of 18.24m2 is sufficient to satisfy the heating demand, while radiator heating requires a panel area of 3.6m2. To meet the same load, the total pipe length for the radiant and radiator heating systems is 300m and 42m, respectively. Radiant and radiator heating systems had a heat transfer coefficient of 7.76W/m2 and 15.34W/m2, respectively. The variation is because the radiator system must provide the same amount of heat to the building while having a smaller surface area than the radiant heating system.

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Wang, Zhangyuan, Zicong Huang, Fucheng Chen, Xudong Zhao, and Peng Guo. "Experimental investigation of the novel BIPV/T system employing micro-channel flat-plate heat pipes." Building Services Engineering Research and Technology 39, no. 5 (January 17, 2018): 540–56. http://dx.doi.org/10.1177/0143624418754337.

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In this paper, the micro-channel flat-plate heat pipes-based BIPV/T system has been proposed, which is expected to have the characteristics, e.g. reduced contact thermal resistance, enhanced heat transfer area, improved heat transfer efficiency and building integration. The proposed system was constructed at the laboratory of Guangdong University of Technology (China) to study its performance. The temperatures of the glass cover, PV panel, micro-channel flat-plate heat pipes, and tank water were measured, as well as the ambient temperature. The thermal and electrical efficiency was also calculated for the system operated under the conditions with different simulated radiations and water flow rates. It was found that the proposed system can achieve the maximum average overall efficiency of 50.4% (thermal efficiency of 45.9% and electrical efficiency of 4.5%) for the simulated radiation of 300 W/m2 and water flow rate of 600 L/h. By comparing the proposed system with the two previous systems employing the conventional heat pipes, the thermal efficiency of the proposed system was clearly improved. The research will develop an innovative BIPV/T technology possessing high thermal conduction capability and high thermal efficiency compared with the conventional BIPV/T system, and helps realise the global targets of reducing carbon emission and saving primary energy in buildings. Practical application: This novel BIPV/T employing micro-channel flat-plate heat pipes will be potentially used in buildings to provide amount of electricity and thermal energy. The generated electricity will be used by the residents for electrical devices, and the thermal energy can be used for hot water, even for space heating and cooling.

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Bég, O. Anwar, Atul Kumar Ray, Rama S. R. Gorla, Henry J. Leonard, Ali Kadir, T. A. Bég, and B. Vasu. "Homotopy Simulation of Dissipative Micropolar Flow and Heat Transfer from a Two-Dimensional Body with Heat Sink Effect." Chemical & biochemical engineering quarterly 34, no. 4 (2021): 257–75. http://dx.doi.org/10.15255/cabeq.2020.1849.

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Non-Newtonian flow from a wedge constitutes a fundamental problem in chemical engineering systems and is relevant to processing of polymers, coating systems, etc. Motivated by such applications, the homotopy analysis method (HAM) was employed to obtain semi-analytical solutions for thermal convection boundary layer flow of incompressible micropolar fluid from a two-dimensional body (wedge). Viscous dissipation and heat sink effects were included. The non-dimensional boundary value problem emerges as a system of nonlinear coupled ordinary differential equations, by virtue of suitable coordinate transformations. The so-called Falkner-Skan flow cases are elaborated. Validation of the HAM solutions was achieved with earlier simpler models, as well as with a Nakamura finite difference method for the general model. The micropolar model employed simulates certain polymeric solutions quite accurately, and features rotary motions of micro-elements. Primary and secondary shear stress, wall couple stress, Nusselt number, microrotation velocity, and temperature were computed for the effect of vortex viscosity parameter (micropolar rheological), Eckert number (viscous dissipation), Falkner-Skan (pressure gradient) parameter, micro-inertia density, and heat sink parameter. The special cases of Blasius and stagnation flow were also addressed. It was observed from the study that the temperature and thermal boundary layer thickness are both suppressed with increasing wedge parameter and wall heat sink effect, which is beneficial to temperature regulation in polymer coating dynamics. Further, strong reverse spin was generated in the microrotation with increasing vortex viscosity, which resulted in increase in angular momentum boundary layer thickness. Also, both primary and secondary skin friction components were reduced with increasing wedge parameter. Nusselt number was also enhanced substantially with greater wedge parameter.

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Budiono, Andres, Suyitno Suyitno, Imron Rosyadi, Afif Faishal, and Albert Xaverio Ilyas. "A Systematic Review of the Design and Heat Transfer Performance of Enhanced Closed-Loop Geothermal Systems." Energies 15, no. 3 (January 20, 2022): 742. http://dx.doi.org/10.3390/en15030742.

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Geothermal energy is one of the primary sources of clean electricity generation as the world transitions away from fossil fuels. In comparison to enhanced geothermal methods based on artificial fracturing, closed-loop geothermal systems (CLGSs) avoid seismicity-induced risk, are independent of reservoir permeability, and do not require the direct interaction between the fluid and the geothermal reservoir. In recent years, the development of CLGS technologies that offer high energy efficiencies has been explored. Research on coaxial closed-loop geothermal systems (CCLGS) and U-shaped closed-loop geothermal system (UCLGS) systems were reviewed in this paper. These studies were categorized based on their design, modeling methods, and heat transfer performance. It was found that UCLGSs had superior heat transfer performances compared to CCLGS. In addition, UCLGSs that utilized CO2 as a working fluid were found to be promising technologies that could help in addressing the future challenges associated with zero-emission compliance and green energy demand. Further research to improve the heat transfer performance of CLGS, especially with regards to improvements in wellbore layout, equipment sizing, and its integration with CO2 capture technologies is critical to ensuring the feasibility of this technology in the future.

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García, E. Martínez, and A. Pullung Sasmito. "Conjugated Heat Transfer Analysis in a Host Rock–Drift System at Deep Underground Mines." Proceedings 2, no. 23 (December 7, 2018): 1428. http://dx.doi.org/10.3390/proceedings2231428.

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On behalf of the European Commission, a ‘critical raw materials’ list has been created, including rare materials susceptible of special location and exploitation thereby their importance in the stability of global economy development and current life quality. This fact, confers primary importance to Geophysics and new ore bodies operation as using of existing reserves in order to be able to supply current requirements of global production. One of the most important effects at underground environment is higher host-rock temperature triggered by geothermal gradient. In addition of this thermal loads, diesel fluxes are also important, as well as air humidity and drift ventilation. Thermal loads analysis for dimensioning cooling systems is strongly influenced by the high thermal inertia of host-rock in underground mines, which involves the appearance of long-term transient processes during the setting up.

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Molinari, Martina, Vincenzo Narcisi, Cristiano Ciurluini, and Fabio Giannetti. "Transient analysis of OSU-MASLWR with RELAP5." Journal of Physics: Conference Series 2177, no. 1 (April 1, 2022): 012018. http://dx.doi.org/10.1088/1742-6596/2177/1/012018.

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Abstract The present paper deals with the assessment of the original and a modified version of RELAP5/MOD3.3 against the OSU Multi Application Small Light Water Reactor (OSU-MASLWR). The new implemented features regard suitable correlations for the heat transfer coefficient evaluation in helical geometry. Furthermore, two different modelling of the Helical Coil Steam Generator (HCSG) are assessed. In the first approach, HCSG’s primary and secondary sides are collapsed in a single pipe component. In the second model, three equivalent pipes are conceived for the simulation of the three ranks composing the HCSG. Two different power manoeuvring experiments are reproduced. The simulations highlight a satisfactory agreement in both the transients. Nevertheless, the modified code shows enhanced capabilities in the prediction of the HCSG operation. This is due to the improvements adopted in the modified version of RELAP5/MOD3.3 that allows a better modelling of the dryout phenomena occurring within helical tubes, as well as a better estimation of the primary side heat transfer coefficient. The better agreement of the heat exchange is propagated to the primary system, resulting in a more accurate prediction of the inlet and outlet core temperatures, and primary flow rate.

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Allouache, Nadia, Rachid Bennacer, Salahs Chikh, A. Al Mers, and N. Mimouni. "Modeling of Heat and Mass Transfer in an Annular Adsorber for Solar Cooling Machine: Performance Coefficients." Defect and Diffusion Forum 312-315 (April 2011): 641–46. http://dx.doi.org/10.4028/www.scientific.net/ddf.312-315.641.

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The primary aim of this study is to simulate numerically the heat and mass transfer characteristics in the annular adsorber that is the most important component of the solar cooling machine, and to evaluate the solar and thermal coefficients of performance as an optimisation criterion of the system, for different adsorbent/adsorbate pairs. The porous medium constituted of the adsorbent/adsorbate is contained in the annular space and it is heated by solar energy. A general model equation is used for modeling the transient heat and mass transfer. The adsorption phenomenon is described by using different models of solid-adsorbate equilibrium. Effects of the key parameters on the adsorbed quantity, the generating temperature, the performance coefficients and thus on the system performances are investigated.

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Maciejewska, Beata, Kinga Strak, and Magdalena Piasecka. "The solution of a two-dimensional inverse heat transfer problem using two methods." International Journal of Numerical Methods for Heat & Fluid Flow 28, no. 1 (January 2, 2018): 206–19. http://dx.doi.org/10.1108/hff-10-2016-0414.

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Purpose This paper aims to focus on flow boiling heat transfer in an asymmetrically heated minichannel. Two-dimensional inverse heat transfer problem was solved using the Trefftz and Beck methods. The primary purpose was to find an enhanced surface that could help intensify heat transfer. Design/methodology/approach The experimental set-up and methodology for FC-72 boiling heat transfer in two parallel vertical rectangular minichannels with smooth or enhanced heated surfaces was presented. The heat transfer coefficient was calculated using the Trefftz and Beck methods. Findings The results confirm that considerable heat transfer enhancement takes place when selected enhanced heated surface is used in the minichannel flow boiling and that it depends on the type of surface enhancement. The analysis of the experimental data revealed that the values and distributions of the heat transfer coefficient obtained using the Beck and Trefftz methods were similar. Practical/implications Many studies have been recently devoted to flow boiling heat transfer in minichannels because of the rapid development of high-performance integrated systems generating large amounts of heat. Highly efficient small-size cooling systems for new-generation compact devices are thus in great demand. Originality/value The present results are original and new in the study of cooling liquid boiling in minichannels with enhanced heated surfaces that contribute to heat transfer enhancement. The paper allows the verification of state-of-the-art methods of solving the inverse problem by using empirical data from the experiment. The application of the Trefftz and Beck methods for finding a solution of the inverse heat transfer problem is promising.

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Chu, Fengming, Minghui Su, and Guoan Yang. "Effects of stripper configurations on mass transfer and energy consumption of regeneration process." International Journal of Low-Carbon Technologies 15, no. 2 (January 20, 2020): 190–201. http://dx.doi.org/10.1093/ijlct/ctz073.

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Abstract The high energy consumption of the regeneration is the main barrier of the CO2 capture system application. The stripper is the primary device for the regeneration process, which involves with the transport process and reactions. It is beneficial for the energy saving to clarify the impacts of the stripper configurations on the heat and mass transfer performance in the stripper. Based on the representative elementary volume method and pseudo-single-liquid model, a novel computational model of heat and mass transfer was developed, in which the H2O transfer process was also taken into account. The simulation results were compared with the experimental data. The effects of the stripper configurations on the heat and mass transfer performance were investigated, and the energy consumption analysis of different strippers under two representative working conditions was carried out. The results show that the height of stripper is dominant in the heat and mass transfer performance, rather than diameter. When the desorbing rate of CO2 is above 50%, the desorbing rate of CO2 increases with the stripper height rising and the specific energy consumption of regeneration process only increases a little.

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Journal articles on the topic 'Primary Heat Transfer System'

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