摘要
针对含分流再压缩和一次再热的超临界二氧化碳布雷顿循环火力发电系统,建立了其数学模型,并用Fortran语言编制了计算程序.通过详细计算,深入分析了分流系数、主压缩机出口压力、主压缩机入口压力、透平入口温度等关键参数对循环效率的影响.结果表明:随着一次工质温度或二次工质温度的升高,循环效率线性升高;但由于超临界二氧化碳物性的特点以及高、低温回热器最小换热温差的约束,主压缩机出、入口压力和分流系数等参数对循环效率的影响均非单调变化,这与传统的蒸汽朗肯动力循环完全不同;超临界二氧化碳动力循环系统存在最优的压缩机出、入口压力和分流系数的耦合关系,使得该系统的循环效率最高.
A mathematical model was established for the supercritical fossil-fired power system with CO2 recompression and reheat Brayton cycles, based on which the effects of following key parameters on the cy- cle efficiency were analyzed through detailed calculation with programs developed on the Fortran platform, such as the split ratio of flow, the inlet and outlet pressure of compressor, inlet temperature of turbine etc. Results show that the cycle efficiency increases linearly with the temperature rise of primary and sec- ondary working medium. Different from traditional Rankine cycles, above parameters in Brayton cycles show non-monotonic relationship with the cycle efficiency due to the features of spercritical CO2 physical properties and the constraints of minimum temperature difference for heat exchange. There exists an opti- mum combination of compressor inlet pressure, compressor outlet pressure and split ratio for supercritical CO2 Brayton cycles, in which case, the cycle efficiency reaches the maximum.
出处
《动力工程学报》
CAS
CSCD
北大核心
2016年第10期827-833,852,共8页
Journal of Chinese Society of Power Engineering
基金
国家自然科学基金资助项目(51406166)
