The effects of ignition timing on residual gas, effective release energy, engine power and emissions characteristics with different speed

摘要

This paper presents a study of residual gas, effective release energy and engine emissions of small engine with variable ignition timing at full load. The study was conducted by simulating the variable ignition timing from 10 to 40 degrees in the full-load operation mode at low speed (3000 rpm), medium speed (5000 rpm) and high speed (8000 rpm) of the engine, then comparing the changes of the residual gas, exhaust gas (NOx, CO, HC) and effective release energy. The results from the simulation showed that the ignition timing had a significant effect residual gas ratio, effective release energy, engine performance, and emission characteristic. When the engine speed at high speed and ignition timing is 10 °CA, the minimum residual gas ratio was 0.07%. At the ignition timing is 40 °CA, the maximum effective release energy was 0.87 kJ. Moreover, at the engine speed at low speed the maximum release energy was 0.635 kJ at 10 °CA of ignition, while the high speed achieved maximum release energy at 40 °CA was 0.848 kJ. The maximum engine brake torque was 20.37 Nm and the minimum BSFC was 334 g/kWh at medium speed and 30 °CA of ignition timing.