Operations Cycle of the Stirling Engine with Particular Reference to the Function of the Regenerator

The basic elements of a Stirling engine, the regenerator and the compression and expansion spaces may be arranged in three different ways. The preferred arrangement is the displacer-piston in a single-cylinder system. With a machine of this type, acting as a refrigerator, some experiments were carried out to determine the effect of the regenerator on the machine output. The experimental regenerators were made up of packs of wire gauze. Different sizes and arrangements of meshes were tried, and it was found that dense meshes with small diameter wires gave the best results. The theory of the operational cycle of a Stirling engine is not fully developed, but a simplified theory can be used to investigate the effects of some of the independent design parameters. A recent more complex theory promises to make possible a closer relation of the experimental and theoretical performance of an engine. The operating conditions of a regenerator in a Stirling engine are different from those assumed in the existing theory of regenerators developed mainly for application to gas turbines. Even so values for the efficiency of the regenerator in a particular case can be estimated using the theory. The few values obtained confirm the conclusions of the experimental work.