Enhancement of Engine Performance and Reduction of Emissions by changing Piston Geometry

Internal combustion engines have been a relatively inexpensive and reliable source of power for applications ranging from domestic use to large scale industrial and transportation applications for most of the twentieth century. DI Diesel engines, having the evident benefit of a higher thermal efficiency than all other engines, have served for both lightduty and heavy-duty vehicles. In DI diesel engines, swirl can increase the rate of fuel-air mixing. Swirl interaction with compression induced squish flow increases turbulence levels in the combustion bowl, promoting mixing. It is evident that the effect of geometry has a negligible effect on the airflow during the intake stroke and early part of the compression stroke. But when the piston moves towards Top Dead Centre (TDC), the bowl geometry has a significant effect on air flow thereby resulting in better atomization, better mixing and better combustion. In CI engine piston shapes on crown is flat and concave combustion chamber, with this geometry we have been running the engine. But here air fuel ratio mixture cannot mix properly. To avoid this we make piston geometry changes. The main object of this project is to investigate the performance technique to enhance the air swirl to achieve betterment in engine performance and emission in a direct injection (DI) single cylinder diesel engine. In order to achieve the swirl intensities in the cylinder, changes on the piston crown has been selected. To increase the swirl, series of experiments were conducted like 2 toroidal grooves piston, 4 toroidal grooves piston, 6 toroidal grooves piston on piston crown and compare the results with normal piston values