Analysis of cycles of air-cooling machines with multi-step compression and expansion

The technique has been developed for estimating and analysing the thermodynamic efficiency of reversible cycles of air-cooling machines of multi-step compression and expansion using the exergy method. Analytical dependences have been obtained, and the influence of initial parameters on the main energy characteristics and thermodynamic efficiency of the cycles, expressed by exergy efficiency, has been analyzed. Numerical studies were carried out with number step compression and expansion from n = 1 to ∞. Shown that with n = ∞ the cycle of the air cooling machines with multi-step compression and expansion were transformed in to Carnot cycle, and with n = 1 it goes into a cycle with isobars supply and removal of heat to the working body. (paper)