Patent attributes
A rotary engine having an insert in a peripheral wall of the stator body, the insert being made of a material having a greater heat resistance than that of the peripheral wall, having a subchamber defined therein and having an inner surface, the subchamber communicating with the cavity through at least one opening defined in the inner surface and having a shape forming a reduced cross-section adjacent the opening, a pilot fuel injector having a tip received in the subchamber, an ignition element having a tip received in the subchamber, and a main fuel injector extending through the stator body and having a tip communicating with the cavity at a location spaced apart from the insert. The subchamber has a volume corresponding to from 5% to 25% of a sum of the minimum volume and the volume of the subchamber. A method of injecting heavy fuel into a Wankel engine is also discussed.