A method of determining at least one fuel characteristic of a fuel provided to a gas turbine engine of an aircraft includes making an operational change, the operational change being effected by a controllable component of a propulsion system of which the gas turbine engine forms a part, and being arranged to affect operation of the gas turbine engine, sensing a response to the operational change; and determining the at least one fuel characteristic based on the response to the operational change.

A gas supply system for a flame module of a spectrometer and a method of controlling a flame module. The gas supply system comprises an oxidant gas supply line for providing a supply of oxidant gas, an oxidant gas flow valve for varying a gas flow rate of an oxidant gas in the oxidant gas supply line, an oxidant gas safety controller configured to control the oxidant gas flow valve, a fuel gas supply line for providing a supply of fuel gas, a fuel gas flow valve configured to control a gas flow rate of a fuel gas on the fuel gas supply line, and a fuel gas safety controller configured to control the fuel gas flow valve. During normal operation, the oxidant gas safety controller is configured to charge an energy storage circuit of the oxidant gas safety controller. In the event of a power failure, a first switch of the oxidant gas safety controller is configured to connect the energy storage circuit to the oxidant gas flow valve, wherein the energy storage circuit is configured to discharge energy to the oxidant gas flow valve to increase the oxidant gas flow rate in order to extinguish a flame of the flame module, and the fuel gas safety controller is configured to close the fuel gas flow valve.

A gas supply system for a flame module of a spectrometer and a method of controlling a flame module. The gas supply system comprises an oxidant gas supply line for providing a supply of oxidant gas, an oxidant gas flow valve for varying a gas flow rate of an oxidant gas in the oxidant gas supply line, an oxidant gas safety controller configured to control the oxidant gas flow valve, a fuel gas supply line for providing a supply of fuel gas, a fuel gas flow valve configured to control a gas flow rate of a fuel gas on the fuel gas supply line, and a fuel gas safety controller configured to control the fuel gas flow valve. During normal operation, the oxidant gas safety controller is configured to charge an energy storage circuit of the oxidant gas safety controller. In the event of a power failure, a first switch of the oxidant gas safety controller is configured to connect the energy storage circuit to the oxidant gas flow valve, wherein the energy storage circuit is configured to discharge energy to the oxidant gas flow valve to increase the oxidant gas flow rate in order to extinguish a flame of the flame module, and the fuel gas safety controller is configured to close the fuel gas flow valve.

The objective of the present invention is to provide a combustion device capable of informing an amount of used gas, in which an air of gas temperature is reflected, to a user and a method of measuring the amount of used gas. To this end, the combustion device includes: a burner configured to burn gas; a blower configured to supply air for combustion to the burner;

gas valves configured to supply gas for combustion to the burner; a gas temperature sensor configured to measure a temperature of gas supplied to the burner or the blower; and a control unit configured to control the number of revolutions of the blower, calculate a first amount of used gas for a present operating heat quantity burned according to a signal input by a user, and compensate the calculated first amount of used gas with a measured gas temperature measured by the gas temperature sensor to calculate a second amount of used gas.

A system and method of accommodating an uncontrolled high thrust condition in a turbofan gas turbine engine includes processing engine data from the turbofan gas turbine engine to determine when a potential for an uncontrolled high thrust condition exists. When the potential for an uncontrolled high thrust condition exists, the engine data are processed to determine whether corrective action for the uncontrolled high thrust condition should be implemented by varying turbofan gas turbine engine effective geometry to (i) increase turbofan gas turbine engine rotational speed or (ii) decrease turbofan gas turbine engine rotational speed. The determined corrective action is automatically implemented.

A system and method of accommodating an uncontrolled high thrust condition in a turbofan gas turbine engine includes processing engine data from the turbofan gas turbine engine to determine when a potential for an uncontrolled high thrust condition exists. When the potential for an uncontrolled high thrust condition exists, the engine data are processed to determine whether corrective action for the uncontrolled high thrust condition should be implemented by varying turbofan gas turbine engine effective geometry to (i) increase turbofan gas turbine engine rotational speed or (ii) decrease turbofan gas turbine engine rotational speed. The determined corrective action is automatically implemented.

A combined heat exchanger including a flue gas cooler heat-transfer unit supplied with cooling fluid by a supply pump and an upstream GGH heat-transfer unit for circulation of circulating fluid with a downstream GGH by a circulation pump is arranged at an outlet of a gas air heater for heat exchange of flue gas from a boiler body for oxyfuel combustion with recirculation flue gases. A low-low temperature ESP is arranged at an outlet of the combined heat exchanger. A heat-exchange-duty adjustment device is arranged to regulate heats exchanged in the heat-transfer units in the heat exchanger such that at least flue gas temperature at the inlet of the low-low temperature ESP is kept to an inlet set temperature.

A combined heat exchanger including a flue gas cooler heat-transfer unit supplied with cooling fluid by a supply pump and an upstream GGH heat-transfer unit for circulation of circulating fluid with a downstream GGH by a circulation pump is arranged at an outlet of a gas air heater for heat exchange of flue gas from a boiler body for oxyfuel combustion with recirculation flue gases. A low-low temperature ESP is arranged at an outlet of the combined heat exchanger. A heat-exchange-duty adjustment device is arranged to regulate heats exchanged in the heat-transfer units in the heat exchanger such that at least flue gas temperature at the inlet of the low-low temperature ESP is kept to an inlet set temperature.

Provided is a dual venturi having: a tubular part; a body part, for opening/closing the flow of secondary air by rotating in the horizontal plane and vertical plane directions, the horizontal plane direction being the cross-sectional direction of the tubular part and the vertical plane direction being perpendicular to the horizontal plane; a central passageway, becoming the passageway for primary air; a damper part, and a damper part-side secondary gas outlet; a driving part, for rotationally driving the damper part in the horizontal and vertical planes; a gas inlet-side primary gas outlet connected openly to the damper part-side primary gas outlet; and a gas inlet for introducing gas into the tubular part via the damper part, which openly connects selectively to the damper part-side secondary gas outlet on the basis of the rotational position of the damper part, and for forming the rotational shaft of the damper part along with the rotational shaft of the driving part.

Provided is a dual venturi having: a tubular part; a body part, for opening/closing the flow of secondary air by rotating in the horizontal plane and vertical plane directions, the horizontal plane direction being the cross-sectional direction of the tubular part and the vertical plane direction being perpendicular to the horizontal plane; a central passageway, becoming the passageway for primary air; a damper part, and a damper part-side secondary gas outlet; a driving part, for rotationally driving the damper part in the horizontal and vertical planes; a gas inlet-side primary gas outlet connected openly to the damper part-side primary gas outlet; and a gas inlet for introducing gas into the tubular part via the damper part, which openly connects selectively to the damper part-side secondary gas outlet on the basis of the rotational position of the damper part, and for forming the rotational shaft of the damper part along with the rotational shaft of the driving part.