有限时间实际蒸汽动力循环热力性能优化

Thermal performance optimization of actual steam power cycle on the basis of finite time

基于有限时间热力学的理论,根据平均温度法建立循环模型,得出在保持无因次功率PN为定值的条件下,使无因次熵产率Sσ达最小的最佳温差方程.分析了实际蒸汽动力循环反映温差的各无量纲量x、y、α和性能参数比β等对循环性能的影响.研究结果表明,在循环不可逆损失一定时,可采用提高高低温热源温度比α、降低性能参数比β的方法来提高功率PN.

Based on the finite time thermodynamic theory,the cycle model for the actual steam power cycle was established according to the average temperature,and the best temperature difference equation was deduced,making the non-dimensional entropy production rate σS minimum when the non-dimensional power PN maintains the set value.The dimensionless quantities x,y,α and β reflecting the temperature differences and the performance parameters ratio were analysed to illustrate how they affect the cycling performances.The research shows that increasing the α or decreasing the β can raise the PN.