Answer
Auto-tuning in MAN B&W ME-series engines (typically integrated via systems like PMI Auto-Tuning) is an automated control feature within the Engine Control System (ECS). It continuously monitors online cylinder combustion pressures via piezoelectric sensors fitted on the indicator cocks and automatically adjusts electronic actuation parameters—such as Variable Injection Timing (VIT) and Variable Exhaust Closing (VEC)—to balance and optimize each cylinder.
The main reasons are:
- Equalize cylinder load so all cylinders produce similar power.
- Maintain correct Pmax and combustion phasing.
- Reduce specific fuel consumption.
- Avoid one cylinder becoming thermally or mechanically overloaded.
- Keep exhaust temperatures more uniform.
- Compensate for changes in fuel quality, ambient/scavenge conditions, injector condition and engine wear.
- Reduce smoke and help optimize NOx/emissions within the approved engine setting.
- Maintain good performance over a wide load range without repeated manual adjustment.