Kalina地热发电循环模型建立及热力性能分析

STUDY ON THE MODEL ESTABLISHMENT AND THE THERMAL PERFORMANCE ANALYSIS OF KALINA CYCLE SYSTEM

以Kalina地热发电循环（KCSll）为研究对象，针对冷热源温度、工质浓度比及循环压力等参数的变化对KCS11循环效率的影响进行研究。基于Engineering Equation Solver（EES）工程软件平台，编写KCSl1运行参数的计算模型。模拟结果与文献中的数据进行对比，拟合程度较好。进一步研究表明，系统运行中氨水浓度应略高于最高效率点所对应的浓度值，且系统压力应等于或略大于最高效率所对应的压力值。通过对冷热源温度、浓度、压力等参数分析，热源温度升高或冷源温度降低10℃，系统循环效率可提高2．0％～3．5％。在特定冷热源温度下，当氨水浓度增加0．10，循环最大效率所对应的压力增大0．8MPa，系统泵耗随之增加，故系统效率存在极值点。因此在系统运行中应考虑氨水浓度与系统压力的匹配，保证系统能够高效运行。

The Kalina cycle system （ KCSll ） for geothermal power plant was investigated based on the simulation program for KCS11 which is compiled by using the engineering equation solver （EES） software. The numerical simulation results agree with the operation parameters of Kalina power plant in the references. The effects of the cold/heat source, ammonia content and pressure on the efficiency of the KCS11 were investigated. The results of study indicated that the ammonia mass fraction should be lower than the optimum value and the pressure should be equal to or slightly higher than the best pressure value. The temperature of heat sources, ammonia mass fraction and pressure are analyzed, the temperature difference of heat sources increases 10 ~C and the absolute value of thermal efficiency increases by 2. 0% -3.5%, fraction of the working fluid increases by 0. 10, and consequently the optimum pressure is needed to increase by about 0. 8 MPa. It is necessary to consider the influences of ammonia mass fraction and pressure, thereby ensure safe and stable operation condition of KCS11.