A Mathematical Description of the Power Loss from Nonequilibrium Regenerative Heat Exchange in the Thermal Machines

摘要

The paper presents the results of the analytical studies on the mechanisms of arising the losses in non-equilibrium regenerative heat exchange (NRHE) between gaseous working medium and the walls of the working cavity, i.e. in the process existing in all thermal machines. Heat exchange occurs in a significant temperature differential; this process is not-equilibrant, which could lead to tangible power losses in the heat machines. The most modem design methodologies of the thermal machines do not consider power losses in NRHE separately from other types of losses, what leads to errors in the performance indicators , wrong constructive solutions and methods of decreasing of the losses in the thermal machines. The paper describes in details the mechanism of arising the NRHE losses and basing on Guoy-Stodola' theorem derives the analytical expression for evaluating of such losses and gives an example of loss assessment in the aerial two-stage compressor. The given analytical expression determines the parameters influencing the value of thermodynamic losses.