Abstract The increased power consumption and continued miniaturization of high-powered electronic components have presented many challenges to their thermal management. To improve the efficiency and reliability of these devices, the high amount of heat that they generate must be properly removed. In this paper, a three-dimensional numerical model has been developed and experimentally validated for several manifold heat sink designs. The goal was to enhance the heat sink's thermal performance while reducing the required pumping power by lowering the pressure drop across the heat sink. The considered designs were benchmarked to a commercially available heat sink in terms of their thermal and hydraulic performances. The proposed manifolds were designed to distribute fluid through alternating inlet and outlet branched internal channels. It was found that using the manifold design with 3 channels reduced the thermal resistance from 0.061 to 0.054 °C/W with a pressure drop reduction of 0.77 kPa from the commercial cold plate. A geometric parametric study was performed to investigate the effect of the manifold's internal channel width on the thermohydraulic performance of the proposed designs. It was found that the thermal resistance decreased as the manifold's channel width decreased, up until a certain width value, below which the thermal resistance started to increase while maintaining low-pressure drop values. Where the thermal resistance significantly decreased in the 7 channels design by 16.4% and maintained a lower pressure drop value below 0.6 kPa.
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Hydrothermal Performance of Liquid Cooled Battery Thermal Management System with Multiple Inlets
Heat transfer and pumping power of water-cooled thermal management systems (TMSs) for lithium-ion batteries (LIBs) in electric vehicles (EVs) are investigated through a three-dimensional computational approach. TMSs are cylindrical shells that cover LIBs. Water flows through the shell and removes heat from LIBs. The focus of this study is to provide practical insights on the effects of number of inlets on the thermal performance and pumping power of TMSs. Two TMSs with one and four inlets at the top of the TMS’s case are considered. Both TMSs include one outlet, which is located at the bottom of the case. The thermal performance of individual TMSs is evaluated by the maximum temperature of the battery cell and the temperature difference across the cell. The thermal performances are described based on the pumping power. Simulations are performed at different flow rates within a laminar regime. Results indicate that both TMSs provide safe operational temperatures for LIBs. However, compared to the one-inlet design, the four-inlet TMS archives the same thermal performance but at a lower pumping power. The lower pumping power is due to lower pressure drop in the four-inlet TMS resulting from flowing water with lower flow rate at individual inlets, and through a shorter path from individual inlets to the outlet, compared with the one-inlet TMS. Minimizing pumping power without any penalty in the thermal performance is significantly beneficial, especially when the TMS is used for a pack of LIBs in EVs.
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- Award ID(s):
- 1914751
- NSF-PAR ID:
- 10332058
- Date Published:
- Journal Name:
- Proceedings of the 9th International Conference on Fluid Flow, Heat and Mass Transfer (FFHMT’22)
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.11159/ffhmt22.190
