Abstract
Large Eddy Simulation (LES) with Smagorinsky model is used to simulate the induction-compression processes of a motored engine within a cycle. A diesel engine constructed with swirl-generating port and dish-type combustion chamber is used as the model engine. LES results are compared with PIV experiment. It is shown that the maximum of swirl number is gotten at 120 Crank Angle (##o## CA) after induction process Top Dead Center (TDC). The swirl velocity is generated by the tangent designed intake port and strengthened by the impingement of discharge onto piston. The turbulence is intensified by intake valve in induction process and is decayed by viscous dissipation in compression process.