Fuel injection system for aircraft engine

A rotary internal combustion engine, comprising:

• an outer body defining a rotor cavity;
• a rotor rotatable within the rotor cavity and in sealing engagement with walls of the outer body and defining at least one chamber of variable volume in the rotor cavity;
• a pilot subchamber defined by the outer body communicating with the rotor cavity;
• a main fuel injector having a tip in communication with the rotor cavity at a location spaced apart from the pilot subchamber, the main fuel injector having a main actuation inlet hydraulically connected to a source of an actuation fluid, a main fuel inlet hydraulically connected to a fuel source, and a main fuel outlet hydraulically connected to the at least one combustion chamber, the main fuel injector defines a main pressure ratio defined as a main outlet pressure at the main fuel outlet to a main inlet pressure at the main fuel inlet;
• a pilot fuel injector having a tip in communication with the pilot subchamber, the pilot fuel injector having a pilot actuation inlet hydraulically connected to the source of the actuation fluid, a pilot fuel inlet hydraulically connected to the fuel source, and a pilot fuel outlet hydraulically connected to the at least one combustion chamber via the pilot subchamber, the pilot fuel injector defines a pilot pressure ratio defined as a pilot outlet pressure at the pilot fuel outlet to a pilot inlet pressure at the pilot fuel inlet;
• and
• an actuation fluid system having a circuit hydraulically connected to the main actuation inlet and to the pilot actuation inlet;
• wherein the actuation fluid system is operable to inject the actuation fluid at a main actuation pressure to the main actuation inlet and to inject the actuation fluid at a pilot actuation pressure to the pilot actuation inlet,
• wherein the main fuel injector and the pilot fuel injector are structurally configured such that the main pressure ratio is different than the pilot pressure ratio and the main outlet pressure is different than the pilot outlet pressure, and/or the actuation fluid system includes a first pressure regulating valve hydraulically connected to the main actuation inlet and a second pressure regulating valve hydraulically connected to the pilot actuation inlet and configured to regulate the main actuation pressure from the actuation fluid system to be different than the pilot actuation pressure from the actuation fluid system such that the main outlet pressure is different than the pilot outlet pressure.