A rotary engine comprised of a pair of counterrotating rotors within a non-rotating outer housing. Each of the rotors is coupled to a common power shaft, one directly and the other through a reversing gear arrangement. Both are driven by the hyper-expansion of combustion gases in a repeating combustion cycle. Each has a generally circular, nearly frictionless working surface perpendicular to the power shaft axis. Each rotor surface defines chambers which rotate past each other. Within such chambers, compressed air and fuel are introduced, mixed, ignited, allowed to hyper-expand (and thus cause the rotation) and exhausted. The power shaft may be connected to a conventional clutch, torque converter, gearbox, differential, alternator or a similar system.

A rotary engine comprised of a pair of counterrotating rotors within a non-rotating outer housing. Each of the rotors is coupled to a common power shaft, one directly and the other through a reversing gear arrangement. Both are driven by the hyper-expansion of combustion gases in a repeating combustion cycle. Each has a generally circular, nearly frictionless working surface perpendicular to the power shaft axis. Each rotor surface defines chambers which rotate past each other. Within such chambers, compressed air and fuel are introduced, mixed, ignited, allowed to hyper-expand (and thus cause the rotation) and exhausted. The power shaft may be connected to a conventional clutch, torque converter, gearbox, differential, alternator or a similar system.

A mud motor, system, and method for using same are disclosed. A mud motor can include a continuously formed power section stator housing having a first end, a second end, and an internal cavity comprising a series of stator lobes and a housing portion passing. The stator lobes can extend from the first end of the power section stator housing until a first end of a transition portion. The transition portion can form a unitary combination with the stator lobes. The mud motor further includes a rotor assembly including a power section rotor having rotor lobes to be disposed completely within the internal cavity. Additional apparatuses, systems, and methods are disclosed.

A mud motor, system, and method for using same are disclosed. A mud motor can include a continuously formed power section stator housing having a first end, a second end, and an internal cavity comprising a series of stator lobes and a housing portion passing. The stator lobes can extend from the first end of the power section stator housing until a first end of a transition portion. The transition portion can form a unitary combination with the stator lobes. The mud motor further includes a rotor assembly including a power section rotor having rotor lobes to be disposed completely within the internal cavity. Additional apparatuses, systems, and methods are disclosed.

An internal combustion engine includes a housing defining an internal cavity, an inner body sealingly moving within the internal cavity for defining at least one combustion chamber of variable volume, a pilot subchamber in communication with the at least one working chamber, an ignition element in communication with the pilot subchamber, a main injector communicating with the at least one combustion chamber, and a pilot injector having a tip in communication with the pilot subchamber. The tip of the pilot injector includes at least a first injection hole defining a first spray direction and a second injection hole defining a second spray direction different from the first spray direction. The first spray direction extends toward the communication between the pilot subchamber and the at least one working chamber. A method of performing combustion in an internal combustion engine is also discussed.

A rotary internal combustion engine including a rotor assembly where at least a first and a second of the combustion chambers have unequal theoretical volumetric ratios. Also, a rotary internal combustion engine including first and second rotor assemblies where at least one of the combustion chambers of the first rotor assembly and at least one of the combustion chambers of the second rotor assembly have unequal effective volumetric compression ratios and/or unequal effective volumetric expansion ratios.

A rotary internal combustion engine including a rotor assembly where at least a first and a second of the combustion chambers have unequal theoretical volumetric ratios. Also, a rotary internal combustion engine including first and second rotor assemblies where at least one of the combustion chambers of the first rotor assembly and at least one of the combustion chambers of the second rotor assembly have unequal effective volumetric compression ratios and/or unequal effective volumetric expansion ratios.

Two rotors with two lobes are eccentrically mounted within the chamber of a two-lobe rotary machine. The rotors have a periphery defined by a the path of the opposing rotor apex.

Two rotors with two lobes are eccentrically mounted within the chamber of a two-lobe rotary machine. The rotors have a periphery defined by a the path of the opposing rotor apex.

A compound engine assembly including an air conduit having an inlet in fluid communication with ambient air around the compound engine assembly, a compressor having an inlet in fluid communication with the air conduit, an engine core including at least one rotary internal combustion engine and having an inlet in fluid communication with an outlet of the compressor, a turbine section having an inlet in fluid communication with an outlet of the engine core and configured to compound power with the engine core; and at least one heat exchanger in fluid communication with the air conduit, each heat exchanger configured to circulate a fluid of the engine assembly in heat exchange relationship with an airflow from the air conduit circulating therethrough. A method of supplying air to a compound engine assembly is also discussed.