A rotary engine having an outer body having an internal cavity with a peripheral wall having an insert opening defined therethrough in communication with the internal cavity, and a plurality of coolant passages defined through the peripheral wall in proximity of the insert opening, a rotor body rotatable within the internal cavity, and an insert removably received in the insert opening of the peripheral wall, the insert having a subchamber defined therein communicating with the internal cavity, with a minimum width of the insert opening being at least 0.75 inches. An outer body for a rotary engine and a method of inspecting in an internal cavity in an outer body of a rotary engine are also discussed; also, a rotary engine including a fuel injector having a tip received in the injector hole of the peripheral wall without protruding in the insert opening.

An internal combustion engine, includes a 1st rotor having two blades, rotating in the circular volume of the motor body block with variable angular speed; a 2nd rotor having two blades, rotating in the circular volume of the motor body block with variable angular speed, a rolling bearing provided between the 1st rotor and the 2nd rotor enables rotation of the 1st rotor and the 2nd rotor on each other; a 1st unidirectional rolling bearing between the 1st rotor and the back cover enables rotation of the 1st rotor and the 2nd rotor at different times and at different extents; a 3rd unidirectional rolling bearing transferring the 2nd rotor's rotation movements to the output shaft is provided on the internal collar of the 2nd rotor; a 4th unidirectional rolling bearing transferring the 1st rotor's rotation movements to the output shaft is provided on the internal collar of the 1st rotor.

An internal combustion engine, includes a 1st rotor having two blades, rotating in the circular volume of the motor body block with variable angular speed; a 2nd rotor having two blades, rotating in the circular volume of the motor body block with variable angular speed, a rolling bearing provided between the 1st rotor and the 2nd rotor enables rotation of the 1st rotor and the 2nd rotor on each other; a 1st unidirectional rolling bearing between the 1st rotor and the back cover enables rotation of the 1st rotor and the 2nd rotor at different times and at different extents; a 3rd unidirectional rolling bearing transferring the 2nd rotor's rotation movements to the output shaft is provided on the internal collar of the 2nd rotor; a 4th unidirectional rolling bearing transferring the 1st rotor's rotation movements to the output shaft is provided on the internal collar of the 1st rotor.

A system for controlling a turbine valve is provided. The system includes a hydraulic pilot valve section being moveable in a first direction and a second direction; a main hydraulic valve section being moveable in a first direction to close the turbine valve and a second direction to open the turbine valve; a position demand indicating a desired position of the turbine valve; a first feedback indicating an actual position of the hydraulic pilot valve section; and aa second feedback indicating an actual position of the main hydraulic valve section. The system also includes a pilot valve error; a main valve error; a turbine valve error; and a pilot valve adjustment moving the hydraulic pilot valve section in response to the turbine valve error. The turbine valve error is repeatedly determined and the pilot valve adjustment repeatedly moves the hydraulic pilot valve section to minimize the turbine valve error.

A system for controlling a turbine valve is provided. The system includes a hydraulic pilot valve section being moveable in a first direction and a second direction; a main hydraulic valve section being moveable in a first direction to close the turbine valve and a second direction to open the turbine valve; a position demand indicating a desired position of the turbine valve; a first feedback indicating an actual position of the hydraulic pilot valve section; and aa second feedback indicating an actual position of the main hydraulic valve section. The system also includes a pilot valve error; a main valve error; a turbine valve error; and a pilot valve adjustment moving the hydraulic pilot valve section in response to the turbine valve error. The turbine valve error is repeatedly determined and the pilot valve adjustment repeatedly moves the hydraulic pilot valve section to minimize the turbine valve error.

A turbine control system is provided for decreasing the response time between readings of the speed of the turbine and changing a valve position in response thereto. The speed control system includes a speed probe that detects the speed of the turbine and a turbine valve that controls the flow of fluid or gas from or to the turbine. A controller receives a speed signal from the speed probe and sends valve position commands to the turbine valve. The controller also sends support functions to the turbine valve. The controller sends the valve position commands at a faster rate than the support functions.

A turbine control system is provided for decreasing the response time between readings of the speed of the turbine and changing a valve position in response thereto. The speed control system includes a speed probe that detects the speed of the turbine and a turbine valve that controls the flow of fluid or gas from or to the turbine. A controller receives a speed signal from the speed probe and sends valve position commands to the turbine valve. The controller also sends support functions to the turbine valve. The controller sends the valve position commands at a faster rate than the support functions.

A method for evaluating load performance of a rotor/stator test coupon, advantageously within a sealable test chamber comprising test fluid. In some embodiments, the test coupon comprises at least a partial length of a PDM stage, and in others the test coupon comprises a splined rotor/stator. The method includes rotating either the rotor section or the stator section, wherein such rotation actuates corresponding rotation of the other of the rotor section and the stator section. on-linear torque in the form of an acceleration torque and/or a braking torque may be applied to either the rotor section or the stator section. Some embodiments include simulating downhole stall conditions via selectively engaging and disengaging a second motor and flywheel to vary rotational torque applied to the test coupon. Load performance of the test coupon may be evaluated over time in such simulated stall conditions.

A method for evaluating load performance of a rotor/stator test coupon, advantageously within a sealable test chamber comprising test fluid. In some embodiments, the test coupon comprises at least a partial length of a PDM stage, and in others the test coupon comprises a splined rotor/stator. The method includes rotating either the rotor section or the stator section, wherein such rotation actuates corresponding rotation of the other of the rotor section and the stator section. on-linear torque in the form of an acceleration torque and/or a braking torque may be applied to either the rotor section or the stator section. Some embodiments include simulating downhole stall conditions via selectively engaging and disengaging a second motor and flywheel to vary rotational torque applied to the test coupon. Load performance of the test coupon may be evaluated over time in such simulated stall conditions.

A method for evaluating load performance of a rotor/stator test coupon, advantageously within a sealable test chamber comprising test fluid. In some embodiments, the test coupon comprises at least a partial length of a PDM stage, and in others the test coupon comprises a splined rotor/stator. The method includes rotating either the rotor section or the stator section, wherein such rotation actuates corresponding rotation of the other of the rotor section and the stator section. A braking torque is applied to the actuated one of the rotor section and the stator section such that load performance of the test coupon may be evaluated. Embodiments include selectively applying non-linear torque to load the test coupon, and evaluating load performance of the test coupon with reference to relative angular positions of the rotor section and the stator section over time.