Thermal management using the bi-disperse porous medium approach

Abstract

Thermal management of distributed electronics similar to data centers is studied using a bi-disperse porous medium (BDPM) approach. The BDPM channel comprises heat generating micro-porous square blocks, separated by macro-pores. Laminar forced convection cooling fluid of Pr = 0.7 saturates both the micro- and macro-pores. Bi-dispersion effect is induced by varying the macro-pore volume fraction Φ_E, and by changing the number of porous blocks N², both representing re-distribution of the electronics. When 0.2 Φ_E 0.86, the heat transfer Nu is enhanced twice (from ~550 to ~1100) while the pressure drop Δp^∗ reduces almost eightfold. For Φ_E < 0.5, Nu reduces quickly to reach a minimum at the mono-disperse porous medium (MDPM) limit (Φ_E → 0). Compared to N² = 1 case, Nu for BDPM configuration is high when N² » 1, i.e., the micro-porous blocks are many and well distributed. The Nu increase with Re changes from non-linear to linear as N² increases from 1 to 81, with corresponding insignificant pumping power increase.