不同工质对太阳能有机朗肯循环系统性能的影响

Effect of Working Fluids on Performance of Solar Organic Rankine Cycles

摘要: 循环工质的特性是影响有机朗肯循环系统性能的重要因素之一,在不同的蒸发温度条件下,选取R600、R600a、R245fa、R236fa、R236ea、R601、R601a、RC318及R227ea共9种有机工质,基于热力学第一定律和第二定律对其热力循环特性进行了计算分析,并对各有机工质的蒸发压力、热效率、功比和不可逆损失等进行了比较.结果表明:R245fa作为太阳能低温热发电朗肯循环系统的循环工质具有较高的热效率和效率,并且产生的系统总不可逆损失较小,是一种较理想的有机工质;其次,R236fa和R236ea作为系统循环工质也具有较为良好的性能.

Abstract: The properties of working fluid have a significant effect on performance of solar organic Rankine cycles (ORC). Taking R600, R600a, R245fa, R236fa, R236ea, R601, R601a, RC318 and R227ea as the working fluids, cycle performance of the ORC system was studied based on the first and the second law of thermodynamics, during which the evaporating temperature, thermal efficiency, work rate and exergy efficiency were respectively calculated and compared. Results show that for a low-temperature solar ORC system, R245fa creates relatively high thermal and exergy efficiency and produces relatively low total inreversable loss, which therefore is recommended as an ideal fluid for the ORC system; secondly, working fluids R236fa and R236ea have also better properties.