S-CO2布雷顿循环太阳能电力淡水系统火用分析

设计一种使用S-CO₂布雷顿循环的太阳能电力淡水系统,对系统的工作原理和结构组成进行介绍,并对系统开展运行性能和火用分析。结果表明,设计工况下系统的输出电功率为233.8 MW,布雷顿循环效率为37.5%,淡水日产量为3981.6 t。增大太阳辐照度有利于提高系统的电力输出和总的能量效率。定工况下的火用分析结果表明,太阳塔集热器中的火用损最大,为303.99 MW,对应的火用效率为64.45%。海水淡化换热器的火用效率最低,且其火用损值也较大。随着太阳辐照度的增加,太阳塔集热器、海水淡化系统换热器和回热器内的火用损均有不同幅度的增加。因此,对于该S-CO₂布雷顿循环太阳能电力淡水系统的后续优化而言,应重点考虑改进这些部件的性能。

EXERGY ANALYSIS OF S-CO2 BRAYTON CYCLE SOLAR SYSTEM FOR ELECTRICITY AND FRESH WATER PRODUCTIONS

S-CO₂ Brayton cycle-based solar system for electricity and fresh water productions is designed. The working principle as well as the configuration of the system is introduced. The operation performance and exergy analyses of the system are carried out. The results show that the output power and Brayton cycle efficiency of the system are 233.8 MW and 37.5%. The daily fresh water output is 3981.6 t. Increasing the solar intensity can improve the output power as well as the overall energy efficiency of the system. The exergy analysis results under the design condition reveal that the exergy loss in the solar tower is the maximum, which is 303.99 MW. Its corresponding exergy efficiency is 64.45%. The exergy efficiency in the heat exchanger of desalination device is the lowest, and the corresponding exergy loss is relatively large. With the solar intensity increased, the solar tower, heat exchanger of desalination device and two recuperators all have varying degrees of exergy loss increase. Hence, for the further optimization of the system, the performances of these components should be given priority.