Multi-dimensional study of the scavenging process in a uniflow scavenged engine

This paper presents the simulation of the scavenging process of a two-stroke, uniflow scavenged diesel engine using multi-dimensional analysis. A three-dimensional model has been developed and the turbulence effects are modeled using the /Kappa/-/epsilon/ model. The momentum, continuity, energy concentration, turbulence kinetic energy, and energy dissipation rate conservation equations are written in finite difference form and solved explicitly in time. During scavenging, the velocity field is presented together with the air concentration contours. The three-dimensional computations are compared with two-dimensional results to study the effect of the valve geometry on the scavenging process. From the air concentration patterns, the scavenging efficiency is computed as a function of the scavenging ratio.