提出了一种新的SOFC/GT/KCS联合循环发电系统,建立了该系统热力性能的数学模型,根据热力学第一定律和第二定律,利用EES软件仿真模拟对系统进行了能量分析、?分析,并研究了空气流率、燃料利用率、燃料流率、压气机压比、水蒸气碳比的变化对联合循环热力性能的影响。研究结果表明,在设定工况下,SOFC的发电效率为49.2%,系统总发电效率为67.6%,系统总火用效率为68.16%;系统的各部件中,火用损失较大的部件依次为SOFC、后燃烧室、燃气轮机、预热器3和余热锅炉;当燃料利用率为0.85时联合循环系统的性能最佳;在一定范围内,随着空气流率、燃料流率或水蒸汽碳比的增加,联合循环系统的能量利用效率均降低。
ABSTRACT:A newsolid oxide fuel cell/gas turbine/ Kalina cycle system (SOFC/GT/KCS) integrated power generation system was proposed. The new system was simulated by using the EES software based on the developed mathematical models, and the system performance was evaluated by the first and second laws of thermodynamics.The parametric study was also conducted to investigate the influenceof the main parameters, such as the flowrate, thefuel utilization factor, thecompressor pressure ratio and the steam-to-carbon ratio on the system performance in detail. The results indicate thattheSOFC electrical, the system overall electricaland the exergy efficiencies reach about 49.2%,67.6% and68.16%, respectively, underthe ratedconditions. It is also found that the largest exergy loss occurs in the waste heat boiler followed by the SOFC, the gas turbine, the HR3, and the after-burner in the system. In addition,there is an optimalfuel utilizationfactor (0.85)to reachthe maximum overall electrical, exergy and the SOFC electrical efficiencies. And the overall electrical and exergy efficiencies can be improved by decreasing the air flow rate, fuel flow rate, andthe steam-to-carbon ratio within the range of parameters studied.