What is the compression temperature of Diesel engine? – Undated 2017 https://www.quora Physics 1062 Adiabatic Compression In a cylinder of diesel engine, air is suddenly compressed by a piston, a process that causes sudden (therefore adiabatically) rise in temperature. The new temperature is high enough the injected fuel ignites immediately without need of a spark plug. Suppose the piston compresses the air to 1/5 of the original volume. Take the initial conditions to be 1 atmosphere, and T1 27 degree C. Find final temperature and pressure T2 and P2.