Study on Flow Characteristics of Working Medium in Microchannel Simulated by Porous Media Model

Micromachines

Han Lin¹  Xiaoxiao Gu²  Yanfeng Xu²  Lihong Xue²  Chunsheng Guo²  Yufan Xue² 

[1] Centre for Translational Atomaterials, Faculty of Science, Engineering and Technology, Swinburne University of Technology, P.O. Box 218, Hawthorn, Victoria 3122, Australia;School of Mechanical, Electrical & Information Engineering, Shandong University, Weihai 264209, Shandong, China;

关键词: microchannel array;    porous media;    numerical simulation;    theoretical research;    experimental validation;   

DOI  :  10.3390/mi12010018

来源: DOAJ

【 摘 要 】

As a phase change evaporator, a microchannel array heat exchanger is of great significance in the field of microscale heat dissipation. The performance of which strongly depends on the flow resistance, capillary force, and other factors. In order to improve the heat dissipation efficiency, it is necessary to perform an in-depth study of the characteristics of microchannel flow using numerical simulation. However, the current simulation model requires high computational cost and long simulation time. To solve this problem, this paper simplifies the numerical simulation of the rectangular parallel array microchannels by building the basic flow model based on the concept of porous media. In addition, we explore the effect of aspect-ratio (AR), hydraulic diameter, inlet velocity, and other parameters of fluid flow behavior inside the microchannels. Meanwhile, a user-defined function (UDF) is formulated to add the capillary force into the model to introduce capillary force into the porous media model. Through the above research, the paper establishes the porous media model for single-phase and gas-liquid two-phase flow, which acts as a simplification of microchannel array simulation without grossly affecting the results obtained. In addition, we designed and manufactured experiments using silicon-based microchannel heat exchangers with different-ratios, and combined with the visualization method to measure the performance of the device and compared them with simulation results. The theoretical model is verified through the suction experiment of array microchannel evaporator capillary core. The simplified model of microchannel array significantly saves the computational cost and time, and provides guidance for the related experimental researches.

【 授权许可】

Unknown