Rotary internal combustion engine with pilot subchamber

An outer body for a non-Wankel rotary engine comprising:

• two axially spaced apart end walls;
• a peripheral wall extending between the end walls and defining an internal cavity therewith for receiving a rotor therein;
• an insert in the peripheral wall of the outer body, the insert being made of a material having a greater heat resistance than that of the peripheral wall, the insert having a pilot subchamber defined therein and having an inner surface bordering the cavity, the pilot 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;
• the insert having an injector opening defined therethrough communicating with the pilot subchamber, the injector opening being sized to receive a tip of a pilot fuel injector therethrough;
• the insert having an ignition element elongated hole defined therethrough communicating with the pilot subchamber and sized to receive an ignition element therein;
• the peripheral wall having a pilot fuel injector elongated hole defined therethrough at a non-zero angle with respect to a surface of an outer wall of the insert and communicating with the pilot subchamber through the injector opening of the insert, the pilot fuel injection elongated hole being sized to directly receive the pilot fuel injector therein;
• and
• the peripheral wall having a main fuel injector elongated hole defined therethrough spaced apart from the insert and sized to receive a main fuel injector therein.

A method of injecting fuel into a non-Wankel rotary engine having rotating chambers each having a volume varying between a minimum volume and a maximum volume with a difference between the maximum volume and the minimum volume defining a displacement volume, the method comprising:

• injecting at most 20% of the fuel into a pilot subchamber defined adjacent to and in sequential communication with each of the rotating chambers and having a pilot subchamber volume of at least 0.5% of the displacement volume and at most 3.5% of the displacement volume;
• igniting the fuel within the pilot subchamber;
• creating a hot wall around the pilot subchamber by providing the pilot subchamber in an insert received in a wall of a stator of the engine, the insert being made of a material more resistant to high temperature than that of the wall;
• partially restricting a flow of the ignited fuel from the pilot subchamber to the rotating chambers;
• and
• injecting a remainder of the fuel into each of the rotating chambers sequentially, independently of and spaced apart from the pilot subchamber.