時間：2011-03-11 23:13來源：藍天飛行翻譯 作者：admin 點擊：次
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fuel dump system (aircraft fuel system). See fuel jettison system. fuel flowmeter (aircraft instrument). An instrument used to show the rate of fuel flowing to an engine. Fuel flowmeters used with modern fuel-injected reciprocating engines are actually pressure gages that measure the pressure drop across the injector nozzles. A popular flowmeter for turbine engines uses a small turbine in the fuel line to the fuel control unit that measures the rate of fuel flow. It converts this flow rate into an electrical signal and sends it to an indicator in the instrument panel. fuel flow transmitter (powerplant instrument). A device in the fuel line between the engine-driven fuel pump and the carburetor that measures the rate of flow of the fuel. The flowmeter transmitter converts the flow rate into an electrical signal and sends it to an indicator in the instrument panel. fuel heater (turbojet airplane fuel system component). A form of fuel-air heat exchanger in which heat is taken from the compressor bleed air and put into the fuel before it flows through the fuel filter. At high altitude, the temperature is so low that water entrained in the fuel precipitates out and freezes on the fuel filter. The fuel heater warms the fuel enough to prevent the water freezing. fuel injection manifold valve (reciprocating engine component). The valve used in a reciprocating engine fuel injection system that takes fuel from the fuel control unit and distributes it to the various injection nozzles. The manifold valve provides a metering force for conditions of low fuel flow, and also provides a positive fuel shutoff when the engine is shut down. By shutting off the fuel at the manifold valve, the lines to the injector nozzles are kept full of fuel. fuel injection system (reciprocating engine). A form of fuel metering system for a reciprocating engine that injects the fuel directly into the cylinder, rather than mixing it with the air before it is taken in through the intake valve. There are two types of fuel injection systems in use, the direct injection system and the continuous-flow injection system. The direct injection system, such as is used in a diesel engine, sprays the fuel into the cylinder under high pressure. The fuel is atomized by the spray for better combustion. The continuous-flow fuel injection system used on many of the modern horizontally opposed aircraft engines is not a true injection system. It meters the fuel and delivers it under a low pressure to the outside of the intake valve. This fuel, along with the necessary air for combustion, is pulled into the cylinder when the intake valve opens. fuel jettison system. The portion of an aircraft fuel system that allows fuel to be dumped from the tanks to lower the landing weight so a safe landing can be made. Some aircraft are certificated with a higher takeoff weight than is allowed for landing. If an emergency requires such an airplane to return for a landing before enough fuel is used from the tanks to lower the weight enough for landing, fuel may be dumped. |
