Sketch T-s and p-v diagrams for the Diesel cycle.

Diesel cycle:

All diesel engine works on diesel cycle. It have four processes. These four processes are as follows

1-2. Reversible adiabatic compression

2-3. Heat addition at constant pressure

3-4. Reversible adiabatic expansion

4-1. Heat addition at constant volume

When air inters in the piston cylinder after that it compresses and gets heated due to compression after that heat addition take place at constant pressure after that power is produces when piston moves to bottom dead center.

From the diagram of P-v And T-s we can understand so easily.