小涡喷发动机排气温度传感器及温度信号放大器的研制

AN INVESTIGATION FOR TEMPERATURE SENSOR APPLIED IN EXHAUST JET OF SMALL TURBOJET ENGINES AND IN AMPLIFIER OF SIGNAL

该温度传感器采用直径φ1.5mm的碰地型铠装热电偶作测温元件,其金属外套管由高温合金GH30制造。这种铠装热电偶短时工作上限为900℃,长期工作上限为800℃,时间常数小于0.3s,能经受发动机振动和高温气动力的作用而可靠地工作。信号放大器采用差动输入式,可与碰地型的热电偶输出信号相配工作,放大器抗干扰能力强,结构紧凑、电气性能好。该系统经飞行试验证明,性能稳定,工作可靠。

The temperature sensor made of high temperature alloy GH30 has a groud-contracted metal-sheathed thermocouple (MST) in diameter of 1. 5mm as its temperature measuring element. The upper temperature limit of this kind of MST is 900℃ for short-time use and 800℃ for long-time use. Its time constant is less than 0. 3s and it operates reliably in engine under vibration and hot aerodynamical conditions. Its signal amplifier is of differential input type and available for output signal of ground-contacted thermocouples. The amplifier also has great anti-interference ability, compact structure and good electrical performances. For this system, stable performances and reliable operation have been proved in flight test.