Thermal energy transfer models in the heat exchange equipment calculations

Abstract

Background: Studies in the field of heat transfer in the heat exchange equipment show significant deviations in calculations when the thermophysical properties of materials are assumed to be averaged. This creates problems in design and reduces the efficiency of heat exchangers.

Objective: Building and implementation of the heat transfer models that consider variations in temperature within the thermal properties of materials, with the goal of enhancing the precision of heat transfer predictions and optimizing the design of heat exchange systems.

Methods: The study utilized numerical analysis of heat transfer considering temperature variations of thermophysical properties. Heat transfer agent mobility and relaxation models were applied. The study included the analysis of density, average flow rate of heat transfer agents, thermal conductivity coefficient, specific heat capacity, relaxation time and free path length. The evaluation methods included mathematical modeling and numerical calculations.

Results: The analysis showed that the use of the models that take into account temperature dependencies significantly improves the accuracy of heat transfer calculations. The heat transfer coefficient, heat transfer agent mobility and relaxation time were found to depend significantly on temperature. Qualitative changes in the mobility of heat transfer agents as a function of temperature and the aggregate state of the material were determined.

Conclusions: The proposed models of mobility and relaxation of heat transfer agents allow to predict heat transfer more accurately, which improves the design of heat exchangers and increases their efficiency in industry. These models can be used for further research and optimization of heat transfer systems.

Keywords

heat transfer / heat exchange equipment / temperature dependence / thermophysical properties / mobility models / heat transfer calculation

References

[1] Features of calculations of heat transfer processes based on models of mobility and relaxation of heat carriers. Edited by A.S. Okhotin. Moscow State Textile University named after A.N. Kosygin. Moscow. 2001:233

[2] Zaiman DM. Models of disorder: theoretical physics of homogeneously disordered systems. Moscow. 1982:591.

[3] Okhotin AS, Maryushin LA, Pimenova EL, Afanasyeva EV. Analysis of the temperature dependences of the diffusivity coefficient of the materials (in Russ.). Energosberezhenie i vodopodgotovka. 2009;57(1):43–46. EDN:JWBVZV

[4] Reisland J. Physics of Phonons. Moscow. 1975:365.

[5] Croxton K. Physics of the liquid state. Statistical Introduction. Moscow. 1978:400.

[6] Okhotin AS. Models of Heat Transfer in Condensed Media. Moscow. 1990:198.

[7] Marushin LA, Tikhonova DA. Heat transfer in materials with a disordered. Structure “Conference on Applied Physics, Information Technologies and Engineering” (APITECH-2019). Journal of Physics: Conference Series. 2019;1399(5). doi: 10.1088/1742-6596/1399/5/055005 EDN:QEDZEX

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