Internal combustion engine with common rail pilot and main injection

A rotary internal combustion engine comprising:

• a first common rail having a first metering or pressure regulating valve in fluid communication therewith;
• a second common rail having a second metering or pressure regulating valve in fluid communication therewith, the first and second metering or pressure regulating valves being settable at different pressure values from one another;
• an outer body having at least two rotor cavities each defined by two axially spaced apart end walls and a peripheral wall extending between the end walls;
• a rotor received in each of the at least two rotor cavities, each rotor being rotatable within the rotor cavity in sealing engagement with the peripheral and end walls and defining at least one chamber of variable volume in the rotor cavity;
• and
• for each of the rotor cavities:
• a pilot subchamber defined in the outer body in fluid communication with the rotor cavity,
• a pilot fuel injector in communication with the pilot subchamber,
• an ignition element positioned to ignite fuel within the pilot subchamber, and
• a main fuel injector in communication with the rotor cavity at a location spaced apart from the pilot subchamber;
• wherein each main fuel injector is in fluid communication with the first common rail and each pilot fuel injector is in fluid communication with the second common rail.

A method of combusting fuel in an internal combustion engine having at least two rotors each defining at least one combustion chamber, the method comprising:

• pressurizing the fuel in a first common rail at a first pressure;
• pressurizing the fuel in a second common rail separate from the first common rail at a second pressure different from the first pressure;
• and
• for each of the rotors of the engine:
• feeding a respective pilot injector with fuel at the second pressure from the second common rail to inject fuel in a respective pilot subchamber,
• igniting the fuel within the respective pilot subchamber,
• circulating the ignited fuel out of the respective pilot subchamber and into the one of the combustion chambers, and
• feeding a respective main injector with fuel at the first pressure from the first common rail to inject fuel into the one of the combustion chambers spaced apart from the respective subchamber.