An Ultra-High Power Two-Phase Jet-Impingement Avionic Clamshell Module

Abstract

Boiling jet impingement heat transfer from a simulated electronic chip to Fluorinert FC-72 within a clamshell avionic module was investigated for dependence upon inlet fluid temperature, nozzle diameter, nozzle to chip spacing, jet velocity, and chip length. The clamshell module was designed and fabricated to accommodate both single and multiple chip boards and to demonstrate the feasibility of an ultra-high power (on the order of several kilowatts) module. Critical heat flux (CHF) was found to be directly dependent upon subcooling and jet velocity, but relatively unaffected by the nozzle to chip spacing variations examined. The effect of varying the chip size was evaluated and found to produce higher CHF values as chip size was decreased. A correlation accounting for both geometric and subcooling effects was adapted to predict the CHF database with a mean absolute error of 9.6 percent. The module is shown to be capable of dissipating a heat load of 12,000 W at a module flow rate of 8.01 × 10−4 m3/s (12.7 gpm), thus eclipsing the current technology available in avionic cooling.