Thermal Performance of a Passive Immersion-Cooling Multichip Module

A Passive Immersion-Cooling Multichip Module (PIMM) for the direct liquid cooling of microelectronic components with dielectric liquids was configured to meet expected Workstation thermal management needs. A laboratory module, internally-filled with fluorinert and containing 9 simulated-chip heaters, was tested for different orientations, fin lengths, and cold-plate temperatures as well as for the effect of dissolved noncondensables. The 80 × 80 × 27 mm module had a "submerged condenser" finned with an array of square pin fins and was found to have a peak heat dissipation capacity of 290 W with a cold-plate temperature of 20 °C. The thermofluid phenomena encountered in the operation of the PIMM and the best available relations for the heat transport from the chips to liquid and from liquid to "submerged condenser" surface are presented.