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Title: Two-phase Impingement Cooling using a Trapezoidal Groove Microchannel Heat Sink and Dielectric Coolant HFE 7000
This paper focuses on two-phase flow boiling of dielectric coolant HFE 7000 inside a copper multi-microchannel heat sink for high heat flux chip applications. The heat sink is composed of parallel microchannels, 200 μm wide, 2500 μm high, and 20 mm long, with 200-μm-thick fins separating the channels. The copper heat sink consists of almost 100 channels connected by a longitude groove with a nearly trapezoidal cross section. Coolant impinges down to the base at the groove and then goes along the microchannels. A copper block heater arrangement was used to mimic a computer chip with a footprint of 1”x1” (6.45 cm2). The base heat flux was varied from 7.75 W/cm2 to 96.1 W/cm2 and the mass flux from 547.6 to 958.4 kg/m2s, at a nominal saturation temperature of 54 °C. Heat transfer coefficients as high as 57.5 kW/m2K were reached, keeping the base temperature under 66 °C with a maximum of 21.9 kPa of pressure drop, for inlet subcooling of 5 degree and a coolant flow rate of 958.4 kg/m2. Effects of inner diameter of tubing on thermal performance and pressure drop are also discussed. It was observed that an increase of tubing inner diameter by 60 % can result in increase of heat transfer coefficient by 47.8 % and reduction in pressure drop by 63 %.  more » « less
Award ID(s):
1941181
NSF-PAR ID:
10398674
Author(s) / Creator(s):
; ; ; ; ; ; ;
Date Published:
Journal Name:
2021 20th IEEE Intersociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems (iTherm)
Page Range / eLocation ID:
237 to 245
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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