Coefficient Of Performance for a non perfectly reversible cooler

Description

Pulse tube cryocooler(or refrigerator) can be made without moving parts in the low temperature part of the device, making the cooler suitable for a wide variety of applications. Stirling-type single-orifice pulse-tube refrigerator will be treated operating with an ideal gas as the working fluid. A piston moves periodically from left to right and back. As a result the gas also moves from left to right and back while the pressure within the system increases and decreases. If the gas from the compressor space moves to the right it enters the regenerator with temperature TH and leaves the regenerator at the cold end with temperature TL, hence heat is transferred into the regenerator material. On its return the heat stored within the regenerator is transferred back into the gas. However, a pulse-tube refrigerator is not perfectly reversible due to the presence of the orifice, which has flow resistance.