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Miniaturization of microelectronic components comes at a price of high heat flux density. By adopting liquid cooling, the rising demand of high heat flux devices can be met while the reliability of the microelectronic devices can also be improved to a greater extent. Liquid cooled cold plates are largely replacing air based heat sinks for electronics in data center applications, thanks to its large heat carrying capacity. A bench level study was carried out to characterize the thermohydraulic performance of two microchannel cold plates which uses warm DI water for cooling Multi Chip Server Modules (MCM). A laboratory built mock package housing mock dies and a heat spreader was employed while assessing the thermal performance of two different cold plate designs at varying coolant flow rate and temperature. The case temperature measured at the heat spreader for varying flow rates and input power were essential in identifying the convective resistance. The flow performance was evaluated by measuring the pressure drop across cold plate module at varying flow rates. Cold plate with the enhanced microchannel design yielded better results compared to a traditional parallel microchannel design. The study conducted at higher coolant temperatures yielded lower pressure drop values with no apparent change in the thermal behavior using different cold plates. The tests conducted after reversing the flow direction in microchannels provide an insight at the effect of neighboring dies on each other and reveal the importance of package specific cold plate designs for top performance. The experimental results were validated using a numerical model which are further optimized for improved geometric designs.
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Thermal-Hydraulic Analytical Models of Split-Flow Microchannel Liquid-Cooled Cold Plates With Flow Impingement
Abstract Impingement split flow liquid-cooled microchannel cold plates are one of several flow configurations used for single-phase liquid cooling. Split flow or top-in/side-exit (TISE) cold plates divide the flow into two branches thus resulting in halved or reduced flow rates and flow lengths, compared to traditional side-in /side-exit (SISE) or parallel flow cold plates. This has the effect of reducing the pressure drop because of the shorter flow length and lower flow rate and increasing the heat transfer coefficient due to thermally developing as opposed to fully developed flow. It is also claimed that the impinging flow increases the heat transfer coefficient on the base plate in the region of impingement. Because of the downward impinging and turning flow, there are no exact analytical models for this flow configuration. Computational and experimental studies have been performed, but there are no useful compact analytical models in the literature that can be used to predict the performance of these impingement cold plates. Results are presented for novel physics-based laminar flow models for a TISE microchannel cold plate based on an equivalent parallel channel flow approach. We show that the new models accurately predict the thermal-hydraulic performance over a wide range of parameters.
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- Award ID(s):
- 1738782
- PAR ID:
- 10341820
- Date Published:
- Journal Name:
- Proceedings of the 2021 ASME InterPACK
- 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/10.1115/IPACK2021-73283
