时间：2011-03-11 23:18来源：蓝天飞行翻译 作者：航空 点击：次
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secondary color. A color produced by combining two primary colors in equal proportions. Green is a secondary color made by mixing equal amounts of two primary colors, yellow and blue. secondary controls of an airplane. Controls that modify the effect of the ailerons, rudder, and elevators of an airplane, and do not in themselves cause rotation of the airplane about any of its three axes. Wing flaps, trim tabs, servo tabs, spring tabs, and antiservo tabs are examples of secondary controls. secondary current (electrical current). Current that flows in the secondary winding of a transformer. Secondary current in a magneto ignition system is the high-voltage current induced in the secondary winding of the magneto coil. It is this secondary current that flows through the distributor and produces the spark at the spark plug. secondary emission (electron tubes). Emission of electrons in an electron tube from an electrode other than the cathode. Secondary emission takes place when electrons traveling at a high velocity strike the anode (plate) and knock other electrons from it. When secondary emission is a problem, a suppressor grid is installed near the anode. A negative voltage on the suppressor grid suppresses the secondary emission by forcing the electrons that have been knocked from the anode, back onto it. secondary fuel (gas turbine engine fuel metering). The main flow of fuel from the fuel nozzles inside a gas turbine engine. Primary, or pilot, fuel is used for starting the engine and for low-speed operation. Secondary fuel allows the engine to produce its maximum power. secondary radar. Radar which responds to pulses of energy transmitted from an interrogator. The response is transmitted on a frequency different from that which was received. secondary standard. A unit of length, weight, voltage, capacitance, time, or other value that is compared with a primary standard to determine its accuracy. Secondary standards are working standards. A clock, for example, is used as a secondary standard for measuring time, and it is calibrated by comparing it to the time signal transmitted by radio station WWV. In this example, the signal transmitted by station WWV is used as the primary standard. secondary voltage. The voltage in an alternating current circuit produced across the secondary winding of a transformer. secondary winding (electrical transformer). The transformer winding connected to the electrical load. The winding connected to the source of electrical energy is called the primary winding. If the secondary winding has more turns than the primary winding, the transformer is a step-up transformer. secondary winding (magneto coil). The winding in a magneto or ignition coil that connects to the distributor rotor. The secondary winding is normally made of very small-diameter wire and has a large number of turns, typically about 20,000. |
