Technical Paper
Improving the Reliability of Piston for Increased Power Density by Changing the Shape of Piston Bowl for a Medium Speed Heavy Duty Diesel Engine
2019-01-09
2019-26-0048
Global development trend in diesel engine is to extract more power from the same engine thereby increasing the brake mean effective pressure (BMEP). With increase in the engine BMEP, maintaining reliability of the pistons and piston ring set becomes challenging as mechanical and thermal loading increases simultaneously. Reliability can be maintained by changing the material to higher grade and/or applying different coatings; however this involves significant cost and development time. It is always preferred to keep the same material and improve the reliability of parts. In this work the BMEP of a heavy duty medium speed diesel engine is increased by 10% (from 22.8 bar BMEP to 25 bar BMEP) without change in the piston or piston ring set material. This is achieved by studying the effect of existing piston bowl shape and then changing the shape to improve the reliability of piston and piston ring set. A systematic 6 step methodology is followed.
