Exergetic efficiency optimization for an irreversible heat pump working on reversed Brayton cycle |
| |
Authors: | Yuehong Bi Lingen Chen and Fengrui Sun |
| |
Institution: | (1) Faculty 306, Naval University of Engineering, Wuhan, 430033, P.R. China;(2) Mechanical Engineering Department, U.S. Naval Academy, Annapolis, MD 21402, USA |
| |
Abstract: | This paper deals with the performance analysis and optimization for irreversible heat pumps working on reversed Brayton cycle
with constant-temperature heat reservoirs by taking exergetic efficiency as the optimization objective combining exergy concept
with finite-time thermodynamics (FTT). Exergetic efficiency is defined as the ratio of rate of exergy output to rate of exergy
input of the system. The irreversibilities considered in the system include heat resistance losses in the hot- and cold-side
heat exchangers and non-isentropic losses in the compression and expansion processes. The analytical formulas of the heating
load, coefficient of performance (COP) and exergetic efficiency for the heat pumps are derived. The results are compared with
those obtained for the traditional heating load and coefficient of performance objectives. The influences of the pressure
ratio of the compressor, the allocation of heat exchanger inventory, the temperature ratio of two reservoirs, the effectiveness
of the hot- and cold-side heat exchangers and regenerator, the efficiencies of the compressor and expander, the ratio of hot-side
heat reservoir temperature to ambient temperature, the total heat exchanger inventory, and the heat capacity rate of the working
fluid on the exergetic efficiency of the heat pumps are analysed by numerical calculations. The results show that the exergetic
efficiency optimization is an important and effective criterion for the evaluation of an irreversible heat pump working on
reversed Brayton cycle. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|