Modeling and Performance Optimization of an Irreversible Two-Stage Combined Thermal Brownian Heat Engine

Entropy

Zemin Ding¹  Congzheng Qi²  Huijun Feng²  Lingen Chen²  Yanlin Ge² 

[1] College of Power Engineering, Naval University of Engineering, Wuhan 430033, China;Institute of Thermal Science and Power Engineering, Wuhan Institute of Technology, Wuhan 430205, China;

关键词: finite time thermodynamics;    thermal Brownian heat engine;    combined cycle;    power output;    efficiency;    performance optimization;   

DOI  :  10.3390/e23040419

来源: DOAJ

【 摘 要 】

Based on finite time thermodynamics, an irreversible combined thermal Brownian heat engine model is established in this paper. The model consists of two thermal Brownian heat engines which are operating in tandem with thermal contact with three heat reservoirs. The rates of heat transfer are finite between the heat engine and the reservoir. Considering the heat leakage and the losses caused by kinetic energy change of particles, the formulas of steady current, power output and efficiency are derived. The power output and efficiency of combined heat engine are smaller than that of single heat engine operating between reservoirs with same temperatures. When the potential filed is free from external load, the effects of asymmetry of the potential, barrier height and heat leakage on the performance of the combined heat engine are analyzed. When the potential field is free from external load, the effects of basic design parameters on the performance of the combined heat engine are analyzed. The optimal power and efficiency are obtained by optimizing the barrier heights of two heat engines. The optimal working regions are obtained. There is optimal temperature ratio which maximize the overall power output or efficiency. When the potential filed is subjected to external load, effect of external load is analyzed. The steady current decreases versus external load; the power output and efficiency are monotonically increasing versus external load.

【 授权许可】

Unknown