Diesel Cycle
2-3: a constant pressure process (instead of a constant volume process) and is the only difference between an idealized Diesel cycle and an idealized Otto cycle.
- Fuel injection for an extended period during the power stroke and therefore maintaining a relatively constant pressure.
- Diesel cycle has a lower thermal efficiency as compared to an Otto cycle under the same compression ratio.
- In general, Diesel engine has a higher thermal efficiency than spark-ignition engine because the Diesel engine has a much higher compression ratio.
- Compression-ignition: very high compression ratio 10 to 20 or even higher.