Liquid Supply and Heat Transfer Performance of Sintered Cu Monolayer Wicks for Phase Change Heat Transfer Applications

When combined with a bi-porous or a vertical liquid artery structure, thin porous layers of high thermal conductivity materials can provide high critical heat flux while maintaining low thermal resistance. They are therefore are very promising for applications in advanced heat pipes and vapor chambers. The present study characterizes the liquid supply and heat transfer performance of monolayers of sintered Cu powders. Three sets of monolayer samples are prepared by sintering Cu powders with different diameters (29, 59, 71 um). The measured heat transfer performance is relatively insensitive to the powder diameter in the low flux regime. At relatively high heat fluxes (> 20 W/cm²) monolayers with the two large diameter powders show similar liquid supply and heat transfer performance while the sample with the smallest powder size shows significantly degraded heat transfer performance due to local dryouts.