Study on Dual-Spark Ignition Rapid Combustion Characteristic of Opposed-Piston Two-Stroke GDI Engine

The mixture formation and combustion process of an opposed-piston two-stroke (OPTS) gasoline direct injection (GDI) engine was carried out by numerical simulation. The effects on in-cylinder combustion and engine performance in different ignition ways of dual-spark ignition have been compared and analyzed. The dual-spark ignition system were installed on cylinder liner could make the in-cylinder combustion more stable and faster. It was benefit for increasing the thermal efficiency and avoiding the knock. Compared with single-spark ignition, dual-spark ignition could shorten flame propagation distance and accelerate flame propagation. Compared with single-spark ignition and synchronous dual-spark ignition models, the rapid combustion period of asynchronous ignition model was shorter, which was helpful to fast burning. In 6000r/min and 15kW full load case, the best ignition angle step of asynchronous ignition was about 10 degrees crank angle (CA). When the initial ignition angle was the same, the ignition angle step of asynchronous ignition was smaller and the antiknock was worse. (C) 2014 The Authors. Published by Elsevier Ltd.