| Otto Cycle
|| Diesel Cycle
| Heat addition process in an Otto cycle is a constant volume process .
|| Heat addition process in a Diesel cycle is constant pressure process .
| Otto cycle is used in petrol engines .
|| Diesel cycle is used in diesel engines.
| For the same compression ratio the efficiency of Otto cycle is more than the diesel cycle.
|| For the same compression ratio the efficiency of diesel cycle is less than Otto cycle.
| Practically , Otto Cycle is less efficient because of the problem of knocking .
|| Diesel Cycle is practically more efficient due to higher compression ratios.