闭式不可逆等温加热修正双布雷顿循环功率与效率特性分析  

Power and efficiency performance analysis on a closed irreversible binary Brayton cycle with two isothermal processes

作　　者：齐伟[1,2,3] 王文华[1,2,3] 陈林根[1,2,3] QI Wei;WANG Wen-hua;CHEN Lin-gen

机构地区：[1]海军工程大学热科学与动力工程研究室,湖北武汉430033 [2]海军工程大学舰船动力工程军队重点实验室,湖北武汉430033 [3]海军工程大学动力工程学院,湖北武汉430033

出　　处：《节能》2018年第2期67-71,共5页Energy Conservation

基　　金：国家自然科学基金(项目编号:51576207)

摘　　要：应用有限时间热力学理论,建立了闭式变温热源不可逆等温加热修正双布雷顿循环模型,推导出循环的无因次功率和效率的解析式。通过数值计算,分析了压气机压比、高低温侧换热器有效度、回热器有效度和燃烧室外侧流体入口温比等特征参数对循环性能的影响。研究结果表明,分别存在一对最优的顶循环压比和底循环压比使循环输出功率和效率取得最大值。提高高低温侧换热器有效度和燃烧室外侧流体入口温比均有利于提高系统输出功率和效率,同时还发现,回热器有效度对该循环功率有影响这一不同于经典热力学结论的新现象。A model of closed irreversible binary Brayton cycle with two isothermal processes coupled to variable-temperature reservoirs is established in this paper by using finite-time thermodynamic theory.The analytical formulae of the dimensionless power output and efficiency of the cycle are deduced.The effects,such as the compressor pressure-ratios,the effectivenesses of the hot-side and cold-side heat exchangers,the effectivenesses of the conventional regenerator as well as the inlet temperature ratio of the external fluid of RCC on the performance are analyzed by detailed numerical examples.The results indicate that there exists optimal compressor pressure-ratios of the topping cycle and the bottoming cycle,which leads to maximum dimensionless power output and maximum efficiency,respectively.The power output and efficiency increase when increasing the effectivenesses of the hot-side and cold-side heat exchangers and the inlet temperature ratio of the external fluid of the RCC.It is also found that the effectiveness of the regenerator do influence the cycle power output,which is different from the conclusion from the classical thermodynamic analysis.

关 键 词：有限时间热力学 等温加热修正双布雷顿循环 功率 效率 最优压比 

分 类 号：TK4[动力工程及工程热物理—动力机械及工程]