CFD analysis of fluid flow inside a pentroof combustion chamber with different piston shapes

Abstract

In the present work a study of in-cylinder flow for spark ignition (SI) engine is carried out, for pentroof head piston geometry with four different configurations of the piston crown. The flow pattern is investigated using commercial software package Fluent 6.3 during intake and compression stroke at different engine speeds. The parameters investigated are turbulent kinetic energy (TKE) and tumble ratio. The nature of computed velocity and TKE contours for flat piston combustion chamber is found to be in good agreement with experimental results (Murali et al., 2010). Furthermore, it is found that piston shape significantly affects the velocity and TKE contours of SI engine during the compression stroke. The combustion chamber with trapezoidal piston shows more TKE and tumble ratio when compared to other pistons at 330 crank angle degree, i.e., near TDC during compression, where turbulence is most essential before ignition.