The Rankine cycle is the ideal prototype of steam engines in use today. The cycle is 1) water heated at constant pressure 2) evaporated to saturated vapor 3 superheated to gas 4) expanded 5) exhausted to condenser 6) condensed. In the steam automobile a step 4b where the steam is throttled down to decrease power. They're two Rankine cycles. The above describes the complete Rankine cycle. There is also an engine Rankine cycle used to evaluate the performance of a steam engine separate of the boiler. I have developed a program to analyze the automobile Rankine cycle. The automobile Rankine cycle is the complete cycle including the boiler, throttle, engine, condenser and compression. The low heat reservoir is assumed that of the saturated fluid at condenser pressure. The following is a screen shot of the steam cycle calculator:
You may download the program if you wish.
Version 2.03