Essay of thermodynamic description and optimization of Ranque effect

摘要

This paper presents a thermodynamic description of Ranque effect. Including expansion and compression works into energy exchange provides a rational explanation of the observed effect. These works are performed by small portions of gas in polytropic processes. Rotational motion of the gas and presence of non-reversibility in the processes of expansion and compression are responsible for energy separation. A mathematical model with the use of the conservation laws and the polytropic expansion process was created. Optimization calculations for various values of the polytropic efficiency coefficient and the Mach number of hot gas outflow were performed. It has been obtained that the optimal relative values of exit-section area and the Mach number of inflowing high-pressure gas are invariant with respect to the values of the parameters mentioned above. Using this result, a practical model for optimizing operation process was elaborated. The efficiency coefficient of expansion work is determined during the optimization process. Using this result a practical technique of operational process has been developed.