A scoping thermal analysis was done to evaluate the general feasibility of capillary pumped heat engines. The analysis was motivated by recent advances in nanoscale materials science that have made it increasingly practical to manufacture high porosity wicks with a median pore diameter on the order of a few nanometers. Capillary pumped heat engines are shown to be generally feasible for wick evaporation rates equivalent to about 1 watt per square centimeter when wick material thermal conductivity on the order of a few W/m-K is assumed. A compact heat engine architecture, referred to as an integrated capillary engine, is introduced.
