Thermomolecular energy convertors—I engine cycles

Abstract

A gaseous heat engine cycle is analysed wherein the gas compression is accomplished without a mechanical input as a result of molecular effusion through a capillary material. Expressions are developed for gas flow rate, engine power output and heat input allowing for large temperature differences and heat transfer through the capillary material. Maximum cycle efficiency is evaluated over a range of operating temperatures. Modifying the cycle to include a gravity potential energy barrier is shown to result in significant improvement in cycle efficiency.