I aim aiming at something simpler. What can we say about the required conditions on Tc, Th, and Tws in the different legs of the cycle?Well, what else can I use...?
In a sense, yes. To give an additional hint: there is a fundamental difference in the behavior of Tws for heat engines and refrigerators.Just to add some more..The problem cannot lie in one of the legs A, B, C or D alone since all those parts also exist in a rectangular heat engine (which supposedly does not have this problem). So, it must be a combination of the legs causing the problem.