An experimental study on ignition timing of hydrogen Wankel rotary engine.

The hydrogen-fueled Wanke rotary engine is a promising power system that has both high power and eco-friendly properties. This work investigated the effect of ignition timing on a dual-spark plugs synchronous-ignition hydrogen-fueled Wankel rotary engine under low speed, part load and lean combustion. The results show that with delaying the ignition timing, CA0-10 is shortened first and then lengthened and CA10-90 is consistently shortened. When the CA50 is located between 35 and 40°CA ATDC, the maximum brake torque can be realized. Besides, the selection of ignition timing needs to consider the "trade-off" relationship between the combustion phase and corresponding in-cylinder pressure. The maximum brake torque ignition timing is between 5 and 10°CA ATDC. And there is also a "trade-off" relationship between stability and thermal load when ignition timing is selected. In addition, HC and NO emissions will not become the problem limiting the power performance of hydrogen-fueled Wankel rotary engine under this operating condition. • A modified synchronous ignition hydrogen Wankel rotary engine was used. • The effect of ignition timing on performance of rotary engine was studied. • The power depends mainly on the in-cylinder pressure near 135°CA ATDC. • Selecting ignition timing needs to weigh the stability and thermal load. • Suitable ignition timing makes CA50 located between 35 and 40°CA ATDC. [ABSTRACT FROM AUTHOR]