热电联产型S-CO_(2)布雷顿循环火用效率分析与优化  

Exergy efficiency analysis and optimization of cogeneration S-CO_(2) Brayton cycle

作　　者：陈建利 夏少军[1] CHEN Jianli;XIA Shaojun(Naval Univ.of Engineering,Wuhan 430033,China)

机构地区：[1]海军工程大学,武汉430033

出　　处：《海军工程大学学报》2025年第2期46-52,共7页Journal of Naval University of Engineering

基　　金：国家自然科学基金资助项目(51976235,51606218);湖北省自然科学基金资助项目(2018CFB708)。

摘　　要：为解决燃气轮机高温烟气直接排放大气环境导致的能量损耗大问题,采用超临界二氧化碳布雷顿循环热电联产装置回收高温烟气余热。首先,基于有限时间热力学理论,考虑有限温差传热、不可逆压缩、不可逆膨胀等因素,建立热电联产型超临界二氧化碳(supercritical CO_(2),S-CO_(2))布雷顿循环模型;然后,以火用效率最大为目标,分析工质质量流率、压比、压缩机效率、透平效率、热导率分配比等参数变化对装置火用效率的影响;最后,在换热器总热导率一定的条件下,以热电联产循环火用效率最大为目标进行优化。结果表明:相比于初始设计点,火用效率提高了14.43%,可通过减小压比,增加回热器和冷却器的热导率分配比,降低加热器和热水换热器的热导率分配比,使得装置火用效率达到最佳。该研究可为燃气轮机高温烟气余热的深度利用提供一种新型解决方案,还可为燃气轮机高温烟气余热驱动的S-CO_(2)布雷顿循环热电联产装置的最优设计提供理论指导。In order to solve the big problem of energy loss caused by direct emission of high temperature flue gas from gas turbine to atmospheric environment,a supercritical carbon dioxide Brayton cycle cogeneration plant was proposed to recover the waste heat from high temperature flue gas.Firstly,based on the theory of finite time thermodynamics,a supercritical carbon dioxide Brayton cycle model of cogeneration was established considering the irreversibility losses of finite temperature difference heat transfer,irreversible compression and irreversible expansion.Then,taking the exergy efficiency as the target,the exergy efficiency of the working medium mass flow rate,pressure ratio,compressor efficiency,turbine efficiency,thermal conductivity distribution ratio and other parameters were analyzed.Finally,under the condition that the total thermal conductivity of the heat exchanger was certain,the exergy cycle efficiency of cogeneration was optimized to the best.The results show that the exergy efficiency has been improved by 14.43% compared to the initial design point.It can be achieved by reducing the compression ratio,increasing the heat transfer coefficient distribution ratio of the regenerator and the cooler,reducing the heat transfer coefficient distribution ratio of the heater and the hot water heat exchanger.The study provides a new solution for the deep utilization of gas turbine high temperature flue gas waste heat,and can serve as theoretical guidance for the optimal design of supercritical carbon dioxide Brayton cycle cogeneration plant driven by gas turbine high temperature flue gas waste heat.

关 键 词：热电联产型 超临界二氧化碳 布雷顿循环 火用效率 

分 类 号：TP242[自动化与计算机技术—检测技术与自动化装置]