Analysis of a combined law power-optimized open Joule-Brayton heat-engine cycle with a finite interactive heat source

Through concurrent employment of the first and Second laws of thermodynamic s, a set of optimum power expressions for the open irreversible Brayton and open Joule-Brayton heat-engine cycles has been obtained. These expressions are applicable to configurations with a finite thermal reservoir in which the values of the source outlet temperatures are forced to interact with th e overall cycle during the power optimization of the cycle's working substa nce temperatures. Use of the concurrent law procedure simultaneously allows both the minimization of internal cycle entropy generation and the maximiz ation of specific cycle work in order to provide the internal cycle operati ng temperatures necessary for power optimization. The study is carried out for open versions of these cycles in which the energy input is provided fro m an external source through a heat exchanger, the conductance of which is optimally allocated with respect to the cycle flow rate. The work includes a novel comparative study of the optimized power output of these cycles bot h with non-interactive and with interactive sources. The results of this st udy conclusively indicate the importance of considering variable (interacti ve) sink outlet temperatures in obtaining the power optimum for these cycle s.