Numerical simulation of heat transfer on combustion chamber of a gasoline direct injection engine

Analysis of heat transfer of combustion chamber of an engine is essential for boundary condition of thermomechanical analysis of cylinder head, cylinder and piston. For thermal simulation, local and time average heat transfer coefficient on distinct part of combustion chamber need. A computational fluid dynamics (CFD) FLUENT is applied to simulate fluid flow, heat transfer, spray and combustion in a direct injection engine. turbulent kinetic energy, dissipation rate and instantaneous heat transfer coefficient (HTC) on the cylinder head, cylinder wall, piston, spark plug, intake and exhaust valves, intake and exhaust port were determined for local average HTC. Maximum HTC occurs on intake valve surface during full cycle. Then, cylinder head region was divided to two parts, intake and exhaust side and each part divide to five sections. Finally, time average HTC on ten regions on combustion chamber, and liner were calculated for thermal analysis. Contour of HTC at ۵۴, ۳۶۲ and ۵۳۰ deg were shown.

Keywords:

GDI , Simulation , HTC