工质线性变比热时空气标准 Lenoir循环热力学分析

摘要

考虑实际循环中工质比热随温度变化的特性，建立了工质比热随温度线性变化时的可逆空气标准Lenoir 循环模型，运用经典热力学理论和方法，结合数值计算对循环进行热力学分析，得到了循环输出功和压缩比、效率和压缩比以及功与效率之间的特性关系。通过与工质比热恒定时的空气标准 Lenoir 循环性能进行分析比较，可知工质的线性变比热特性对 Lenoir 循环的热力学性能有较大的影响。所得结论对该循环的应用有一定指导作用。%Considering the effects of variable specific heats of working fluid on the performance of practical cy-cle,a thermodynamic model of a reversible air-standard Lenoir cycle with the linear relation between specific heat of working fluid and its temperature was established by using the classical thermodynamics.The relations between the work output and the compression ratio,between the efficiency and the compression ratio,as well as between the work output and efficiency were derived by detailed numerical examples.Moreover,by compa-ring with the thermodynamic performance of air-standard Lenoir cycle with constant specific heats of working fluid,it was known that the effected of variable specific heats of working fluid on the cycle performance were obvious.The results may provide some guidelines for the application of the Lenoir cycle.