Forced convection and flow boiling of a dielectric liquid in a foam-filled channel

Abstract

Porous metal foams, inserted into the channels of a liquid cold plate, can be used to enhance forced convection and flow boiling heat transfer and may be especially useful for direct, dielectric liquid cooling of electronic and photonic components. This study explores the thermofluid characteristics of three porous copper foam configurations: 95% porosity and 10 PPI, 95% porosity and 20 PPI, and 92% porosity and 20PPI, which were soldered to the heated wall of a 10 mm wide x 37 mm long and 7 mm high channel. The results for water are in good agreement with the available sparse porous matrix correlations, using the recommended dispersion conductivity coefficient of 0.06. Despite this relatively low dispersion coefficient, the porous foam is found to more strongly enhance the convective heat transfer coefficients for FC-72 than water. For the two-phase heat transfer rate, the high porosity and large pore size foam, i.e. the 95%, 10 PPI copper foam, was found to provide the best result, achieving a 10 kW/m <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> -K heat transfer coefficient.