Ram-Tuned and Air-Assisted Direct Fuel Injection Systems Applied to a SI Two-Stroke Engine

This paper describes the operation and performance of two direct fuel injection strategies, namely a ram-tuned injection system (single fluid) and an air-assisted injection system (twin fluid). The injection systems are tested on a 500 cm³ single-cylinder cross scavenged two-stroke cycle engine during part load operation at 1600 rev/min. Particle sizing tests are presented for each injection system, in conjunction with specific emissions and performance results for firing engine tests.