Numerical Analysis of the Performances of a Small Two-Stroke Engine with Direct Injection

World-wide attention to environmental issues in recent years has resulted in a greater demand for cleaner engines, especially with regards to the two-stroke. Considering the techniques for reduction of exhaust emissions the direct injection of fuel into the combustion chamber adapted for a loop scavenged cylinder seems to be an advantageous method.

This paper describes the application of advanced experimental and computational techniques to evaluate mixture formation produced on a commercial engine by means of a direct fuel injection strategy, namely a ram-tuned injection system. The injection system data are experimental while air flow and fuel air mix for the direct injection engine are calculated using a turbulent model of the three dimensional code FLUENT.

Extension of a first work in this field is presented.

In particular two possible strategies to simulate direct injection are tested. The influence of different boundary conditions on the scavenging process was examined too.

A time dependent simulation strategy considering the moving piston is the final step of the work.