3-DIMENSIONAL MODELING OF FLUID-FLOW IN A 4-STROKE COMPRESSION IGNITION ENGINE

This paper presents the analysis of three-dimensional calculations of flow field development in a four-stroke compression ignition (CI) engine during the compression process. The calculations are performed with a modified multidimensional arbitrary mesh using finite difference hydrodynamic model. A post processor has been developed to generate in-cylinder flow characteristics. Computations are carried out with a computing mesh of 4152 cells for a crank angle duration of 90 degrees requiring 17000 of CPU time on a SIEMENS 32 bit mainframe computer. Results reveal an increase in swirl velocities and decrease in axial velocity of the fluid. Formation of squish induced vortices are observed near TDC. A comparison of average cylinder pressure obtained through three-dimensional computations and experimental values from a motored engine showed good agreement validating the prediction.