Investigation of the Effects of Air-cell Creation and Cylinder Walls Insulation in a DI Diesel Engine

A Computational Fluid Dynamics code has been utilized to investigate the effect of air-cell creation inside the piston and cylinder walls insulation on combustion characteristics and exhaust emissions in a direct injection diesel engine. The utilized model includes detailed spray atomization, mixture formation and distribution which enable modeling the combustion process in spray/wall and spray/swirl interactions along with flow configurations. The analyses consider the full load condition in a constant engine speed. The predicted results for mean in-cylinder pressure and emissions are compared to the experimental results and show good agreements. The early obtained results indicated thatinsulation of the engine increased the power and IMEP and decreased the ISFC. Creating the air-cell has a slight effect on improvement of performance parameters but its significant effect is on Soot reduction and decreased the Soot emission as a factor of two.

Keywords:

Air-Cell , Cylinder Insulation , CFD , Emission , Combustion Process