Miniaturization and high heat flux of power electronic devices have posed a colossal challenge for adequate thermal management. Conventional air-cooling solutions are inadequate for high-performance electronics. Liquid cooling is an alternative solution thanks to the higher specific heat and latent heat associated with the coolants. Liquid-cooled cold plates are typically manufactured by different approaches such as: skived, forged, extrusion, electrical discharge machining. When researchers are facing challenges at creating complex geometries in small spaces, 3D-printing can be a solution. In this paper, a 3D-printed cold plate was designed and characterized with water coolant. The printed metal fin structures were strong enough to undergo pressure from the fluid flow even at high flow rates and small fin structures. A copper block with top surface area of 1 inch by 1 inch was used to mimic a computer chip. Experimental data has good match with a simulation model which was built using commercial software 6SigmaET. Effects of geometry parameters and operating parameters were investigated. Fin diameter was varied from 0.3 mm to 0.5 mm and fin height was maintained at 2 mm. A special manifold was designed to maximize the surface contact area between coolant and metal surface and therefore minimize thermal resistance. The flow rate was varied from 0.75 L/min to 2 L/min and coolant inlet temperature was varied from 25 to 48 oC. It was observed that for the coolant inlet temperature 25 oC and aluminum cold plate, the junction temperature was kept below 63.2 oC at input power 350 W and pressure drop did not exceed 23 Kpa. Effects of metal materials used in 3D-printing on the thermal performance of the cold plate were also studied in detail.
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Experimental Characterization of Cold Plates used in Cooling Multi Chip Server Modules (MCM)
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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- Award ID(s):
- 1738793
- NSF-PAR ID:
- 10058150
- Date Published:
- Journal Name:
- 18th Intersociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems, San Diego,
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
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- The DOI is not currently available.
