FEATURES OF HEAT TRANSFER IN A FLAT POROUS MICROCHANNEL


  • A.A. Avramenko Institute of Engineering Thermophysics, National Academy of Sciences of Ukrain e
  • N.P. Dmitrenko Institute of Engineering Thermophysics, National Academy of Sciences of Ukraine
  • Yu.Yu. Kovetska Institute of Engineering Thermophysics, National Academy of Sciences of Ukraine
  • E.A. Kondratieva Institute of Engineering Thermophysics, National Academy of Sciences of Ukraine
Keywords: heat transfer, microchannel, porous medium.

Abstract

A steady heat transfer process of mixed convection in a flat vertical porous microchannel is considered.

The results of simulation showed that Knudsen number effects are more significant in the neighborhood of the wall where growth of Knudsen numbers is accompanied with the velocity and temperature jumps on wall. With increasing parameter of porosity M (decreasing permeability), the flow velocity decreases and the velocity jump decrease as well.

For all combinations of the criteria Ra, Kn and M increasing Knudsen number reduces heat transfer intensity. This can be attributed to increasing temperature jump on wall which causes deterioration of thermal interaction between the fluid and the wall.

For low Rayleigh numbers increasing parameter M leads to increasing heat transfer since the temperature jump decrease on walls. For large Rayleigh numbers the trend becomes reversed, since for larger parameters M, the near-wall velocity decreases.

For low Rayleigh numbers increasing the Knudsen number leads to decreasing hydraulic resistance coefficient, but with increasing parameter M leads to increasing this coefficient. At high Ra numbers increasing Knudsen number leads to growth of hydraulic resistance, which is due to increasing velocity gradient on the wall.

References

1. Jun Jie Liu, Hua Zhang, S. C. Yao, Yubai Li. Porous Media Modeling of Two-Phase Microchannel Cooling of Electronic Chips With Nonuniform Power Distribution. Journal of Electronic Packaging. – 2014. – V.136, № 2. – 021008.
2. Коновалов Д.А. Экспериментальные исследования тепломассопереноса в микроканальных теплообменных элементах. Инженерно-физический журнал. – 2016. – Т. 89, № 3. – С. 625 – 631.
3. Власов М.Н., Корсун А.С., Маслов Ю.А., Меринов И.Г., Рачков В.И., Харитонов В.С. Определение параметров интегральной модели турбулентности применительно к расчёту обтекания стержневых сборок в приближении пористого тела. Теплофизика и аэромеханика. – 2016. – Т.23, № 2. – С. 209 – 218.
4. Kuznetsov A.V., Avramenko A.A. A minimal hydrodynamic model for a traffic jam in an axon. International Communications in Heat and Mass Transfer. – 2009. - V.36, №1. – P. 1 – 5.
5. Kuznetsov A.V., Avramenko A.A. Stability analysis of bioconvection of gyrotactic motile microorganisms in a fluid saturated porous medium. Transport in porous media. – 2003. – V. 53, №1. – Р. 95 – 104.
6. Avramenko A.A., Kuznetsov A.V. The onset of convection in a suspension of gyrotactic microorganisms in superimposed fluid and porous layers: effect of vertical throughflow. Transport in porous media. – 2006. – V. 65, №2. – P. 159 – 176.
7. Kuznetsov A.V., Avramenko A.A. A 2D analysis of stability of bioconvection in a fluid saturated porous medium—estimation of the critical permeability value. International Communications in Heat and Mass Transfer. – 2002. V. 29, № 2. P. 175 – 184.
8. Avramenko A.A., Tyrinov A.I., Shevchuk I.V., Dmitrenko N.P., Kravchuk A.V., Shevchuk V.I. Mixed convection in a vertical flat microchannel . International Journal of Heat and Mass Transfer. – 2017. – № 106. – Р. 1164 – 1173.
9. Avramenko A.A., Kuznetsov A.V., Basok B.I., Blinov D.G. Investigation of stability of a laminar flow in a parallel-plate channel filled with a fluid saturated porous medium. Physics of Fluids. – 2005. – V.17, №9. - P. 094102–1 – 094102 – 6.
10. Vargas M., Sierra F.Z., Ramos E., Avramenko A.A. Steady natural convection in a cylindrical cavity. International communications in heat and mass transfer. – 2002. – V.29, №2. – Р. 213 – 221.
11. Коновалов Д.А. Моделирование теплогидравлических характеристик микроканальных теплообменных элементов на основе матрицы монокристаллов К . «Наука. ИННовацИИ. ТехНологИИ» . – 2017. – № 3. – С.29-40
12. Maziar Dehghan, Mohammad Sadegh Valipour , Seyfolah Saedodin . Microchannels enhanced by porous materials: Heat transfer enhancement or pressure drop increment. Energy Conversion and Management . – 2016. – № 110. – P. 22–32.
13. Gad-el-Hak M. The fluid mechanics of microdevices, J. Fluids Engineering, 1999, V. 121, №1, P.5 – 33.
14. Nield D.A., Bejan A. Convection in Porous Media . Springer Science, USA. – 2006. – 640p.
15. Tao, L.N. On combined free and forced convection in channels. J. Heat Transfer. –1960. – 82(3). –P. 233–238.

Abstract views: 77
PDF Downloads: 35
Published
2020-04-12
How to Cite
Avramenko, A., Dmitrenko, N., Kovetska, Y., & Kondratieva, E. (2020). FEATURES OF HEAT TRANSFER IN A FLAT POROUS MICROCHANNEL. Thermophysics and Thermal Power Engineering, 42(1), 12-18. https://doi.org/https://doi.org/10.31472/ttpe.1.2020.1
Section
Heat and Mass Transfer Processes and Equipment, Theory and Practice of Drying