超声导波谐振式温度传感器设计

The design of ultrasonic guided wave resonance temperature sensor

为实现高温环境下对温度的精准测量,设计了一种基于超声测温原理的谐振式温度传感器。该传感器采用纵向导波激励,敏感元为半波长圆柱谐振器。声波导和谐振器之间采用1/4波长圆锥聚能器过渡,采用一体式加工提高了声耦合效率。敏感元谐振频率和被测环境温度呈单调函数,通过将温度测量转换为频率测量提高了测温精度。为验证该传感器模型,选用直径为3 mm、长度为1 m的铁铬合金丝(牌号0Cr25Al5)制作超声温度传感器,通过高温实验获得了传感器性能数据。实验结果表明该传感器在900℃高温环境下分辨率达到了0.21%,重复性为99.03%,在实际工程中可以作为一种测温方案被采用。

In order to realize the accurate measurement of temperature in high temperature environment,a resonant temperature sensor based on the principle of ultrasonic temperature measurement is designed.The sensor adopts longitudinal guided wave excitation and the sensitive element is a half-wavelength cylindrical resonator.The one-quarter wavelength cone shaped energy collector is used for the transition between the waveguide and the resonator.The resonant frequency of the sensitive element and the measured ambient temperature are monotone functions.In order to verify the sensor model,the ultrasonic temperature sensor was made of ferrochrome alloy with a diameter of 3 mm and a length of 1 m(brand 0 Cr25 Al5),and the performance data of the sensor were obtained through high temperature experiments.The experimental results show that the resolution of the sensor is 0.21%and the repeatability is 99.03%at 900℃.