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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The temperature of the gases after they have passed through the turbine is easy to measure, and this temperature relates to that of the gases at the turbine inlet. The EGT system consists of a number of thermocouples connected in parallel and arranged around the tail pipe so they measure the average temperature of the exhaust gases. EGT indicating system (reciprocating engine). A system for measuring the exhaust gas temperature (EGT) of a reciprocating engine to give the pilot an indication of the efficiency with which the fuel-air mixture inside the cylinders is burning. A thermocouple mounted in the exhaust stack just a few inches from the cylinder measures the temperature of the exhaust gases as they leave the cylinder. The fuel-air mixture that produces the highest EGT contains 15 parts of air to one part of fuel, by weight. The pilot can lean the fuel-air mixture while watching the EGT indicator until the EGT peaks (reaches its highest point and then starts back down). When the temperature peaks, the engine is burning a fuel-air mixture of 0.067 (an air-fuel ratio of 15:1). By enriching the mixture (adding more fuel) until the temperature drops a specified amount, the pilot knows the fuel-air mixture is correct to develop the most efficient operation without danger of detonation. EGT indicator. A thermocouple-type instrument that shows the temperature of the gas leaving the exhaust valve of a reciprocating engine or in the tail cone of a turbine engine. EGT of a reciprocating engine is measured by a chromel-alumel thermocouple probe inserted into one or more exhaust pipes near the cylinder. EGT of a turbine engine is measured by averaging the output of a series of chromel-alumel thermocouples connected in parallel and arranged around the tail cone just aft of the last stage of turbine. EHSI (electronic horizontal situation indicator). An electronic flight instrument that displays navigation information on a multicolor display. An EHSI is used in conjunction with an EADI. |
