1.) Try Energy and Exergy analysis of simple rankine cycle.
2.) Try Energy and Exergy analysis IC engine for analysing optimum speed.
3.) Exergy analysis of Organic Rankine cycle.
These all are numerical problems but you can always validate your obtained results with some experimental data.
Try to download some papers related to above topics (i am also attaching some for your help). Read those papers by giving a lot of time. Understand each and every line and then go for your fomulation.