A fuel supply control device is provided in which a parallel flow path of an orifice and a pressurizing valve is used as a complex pressurizing valve for a fuel supply amount, and which controls a fuel supply pump on the basis of a pressure difference before and after the complex pressurizing valve that has been detected by a pressure difference meter. When the rotational speed of the fuel supply pump is below a predetermined threshold value, the fuel supply pump is controlled on the basis of a first fuel measurement amount, and the fuel supply pump is controlled on the basis of a second fuel measurement amount.

A fuel supply system includes a low flow circuit that branches off parallel to the main flow circuit from the upstream main flow line upstream of the metering valve and has an upstream low flow line having a line connected to an orifice having an upstream side and a downstream side. The downstream side of the orifice is connected to a mass flow meter. A return low flow line is downstream of the mass flow meter and connected into the downstream main flow line at a downstream point. A controller is programmed to take in a low flow circuit mass flow measured by the mass flow meter, and calculate a main mass flow through the main flow circuit and the total mass flow delivered to the engine. A gas turbine engine and a method of operation are also disclosed.

A multi-redundancy electromechanical servo system for regulating a liquid rocket engine, comprising a triple-redundancy servo controller (1), a double-redundancy servo driver (2), double-winding electromechanical actuators (4, 5), a triple-redundancy position sensor (6), a thrust regulator (8) and a mixed ratio regulator (9). Engine thrust, a mixed ratio regulation instruction and a feedback signal of the triple-redundancy position sensor are inputted to the triple-redundancy servo controller, and the triple-redundancy servo controller outputs thrust and mixed ratio regulation PWM wave control signals to the double-redundancy servo driver. The double-redundancy servo driver outputs a three-phase variable-frequency variable-amplitude sine wave current to drive the double-winding electromechanical actuators to drive the thrust regulator and the mixed ratio regulator to move, thus achieving engine thrust and mixed ratio regulation. The present servo system has a simple system and excellent control characteristics, has the ability to “control a two-degree fault operation and drive a one-degree fault operation”, and significantly improves the reliability and usage maintainability of the thrust and mixed ratio regulation of the liquid rocket engine. Also disclosed is a method for implementing the foregoing multi-redundancy electromechanical servo system.

A fuel supply control device controls a fuel supply pump based on a front-rear differential pressure across a metering valve for a fuel supply amount, which is detected by a differential pressure gauge, using parallel flow passages of an orifice and a pressurizing valve as the metering valve, in which the fuel supply control device includes a first control amount generation unit generating a first control amount based on the front-rear differential pressure, a second control amount generation unit generating a second control amount based on the rotation speed of the fuel supply pump, a control amount selection unit, a subtractor, and a control calculation unit, in which the control amount selection unit selects the first control amount in a case where the rotation speed is equal to or lower than a predetermined threshold and select the second control amount in a case where the rotation speed exceeds the threshold.

A bleed valve includes a housing with an inlet coupled to an outlet by a duct, a guide tube with an orifice fixed in the housing between the inlet and the outlet, a piston, and baffle. The piston is slideably supported on the guide tube and is movable between an open and a closed position, the duct fluidly coupling the inlet and outlet in the open position, the duct fluidly separating the inlet and outlet in the closed position. The orifice fluidly couples the inlet and outlet in the open and closed positions to move piston between the open and closed positions according to differential pressure between the bleed valve inlet and outlet. The baffle is slideably supported by the guide tube to set the differential pressure at which the piston moves between the open and closed positions. Gas turbines and differential pressure adjustment methods are also described.

The method can include determining a mass flow rate W of working fluid circulating through the compressor stage, determining a control parameter value associated to the geometrical configuration of the variable geometry element based on the determined value of mass flow rate W; and changing the geometrical configuration of the variable geometry element in accordance with the determined control parameter value.

A method for controlling a hydraulic pumping system that includes a centrifugal pump operating at a functional point. The method uses parameters of the centrifugal pump at the functional point and end-of-lines characteristics of the centrifugal pump to determine an updated Net Positive Suction Head Required, NPSH.sub.r, value.

Methods, apparatus, systems, and articles of manufacture are disclosed to detect air flow separation of an engine. An example apparatus includes hardware, and memory including instructions that, when executed, cause the hardware to at least determine an inlet flow separation parameter based on a first pressure value from a first pressure sensor included in a nacelle of a turbofan and a second pressure value from a second pressure sensor included in the nacelle, determine a severity level parameter based on the inlet flow separation parameter, the severity level parameter based on a difference between the first pressure value and the second pressure value, and adjust a contribution of airflow from aft of a fan of the turbofan based on the severity level parameter.

A component for a gas turbine engine, comprising: a first wall defining an exterior surface of the component; a second wall, arranged such that a coolant channel is defined by the space between the first and second walls; and a plurality of apertures provided through the first wall to connect the coolant channel to the exterior surface of the component; wherein adjacent at least one aperture the coolant channel comprises a flow modifier, configured to locally change the pressure of the coolant flowing in the coolant channel in the region of the aperture relative to a region of the coolant channel adjacent another aperture.

A method for leak detection in a system including a compressor. A first pressure differential is determined in the system via a first pressure differential indicator (PDI). The first pressure differential is converted into a first flow measurement. A second flow measurement is determined downstream of the compressor using a second PDI. The first flow measurement and the second flow measurement are compared to determine whether a leak exists between the first PDI and the second PDI.