Effect of Heat Transfer Law on the Ecological Optimization of a Generalized Irreversible Carnot Engine

Abstract

The optimal ecological performance of a irreversible Carnot engine with the losses of heat-resistance, heat leak and internal irreversibility, in which the transfer between the working fluid and the heat reservoirs obeys a generalized heat transfer law Q ∝ ∆(T n ), is derived by taking an ecological optimization criterion as the objective, which consists of maximizing a function representing the best compromise between the power and entropy production rate of the heat engine. Some special examples are discusses. A numerical example is given to show the effects of heat transfer law, heat leakage and internal irreversibility on the optimal performance of the generalized irreversible heat engine. The results can provide some theoretical guidance for the designs of practical engine.

On the Dynamic Robustness of a Non-Endoreversible Engine Working in Different Operation Regimes

“…It is possible to show, from Equations (28)(29)(30)(31), that f x , g y < 0, while f y , g x > 0. Consequently, A, B, and D are positive.…”

“…Several papers of ecological performance for irreversible engines have been written [26][27][28][29][30][31]. When we use this criteria of optimization, the power output satisfies P Emax ≈ 3/4P Pmax , and the entropy production is σ Emax ≈ σ Pmax /4.…”

Generalized irreversible heat-engine experiencing a complex heat-transfer law

“…1. The following assumptions are made for this model [8,[19][20][21][22][38][39][40][41][42]:-• The working fluid flows through the system in a quasistatic-state fashion. The cycle consists of two isothermal-processes and two adiabatic-processes.…”

“…[20][21][22][23]. The effects of the linear phenomenological heat-transfer law, generalized radiative heat-transfer law and generalized convective heat-transfer law on the ecological optimal performance were analyzed by Chen et al [40] and Zhu et al [41,42].…”

Optimization performance and thermodynamic analysis of an irreversible nano scale Brayton cycle operating with Maxwell–Boltzmann gas

“…This criterion is described as ECF = W À T 0 S gen where W is defined as the work output, T 0 stands for an environment temperature and S gen represents entropy generation. There are a number of ecological functions based on the papers in the open literature [5][6][7][8][9][10][11][12][13][14] which consider the ecological functions for optimization procedure. For example EPC ¼ Ex…”