Abstract: Performance analysis on power density of a real regenerated Brayton cycle coupled to variable-temperature heat reservoirs was performed using finite-time thermodynamics. The analytical formulas about the relations between power density and pressure ratio were derived. In the analysis, the irreversibilities involved the heat resistance losses in the hot and cold-side heat exchangers and regenerator, the irreversible compression and expansion losses in the compressor and turbine, and the pressure losses in the piping. Some parameters of cycle corresponding to the maximum power density were compared with the same parameters corresponding to the maximum power by numerical examples.

Key words: Heat flow calculation;Brayton cycle, Power density;Irreversible process

摘要： 用有限时间热力学方法分析变温热源条件下不可逆回热式布雷顿循环的功率密度特性 ,计入工质与高、低温侧换热器的热阻损失 ,压气机、涡轮机的不可逆压缩和膨胀损失和管路系统中的压力损失 ,导出了功率密度与压比间的解析式 ,并通过数值计算将对应于最大功率密度时的一些参数与对应于最大功率时的同样参数进行了比较。

关键词: 热流计算;布雷顿循环;功率密度;不可逆过程