曲面结构上薄膜热流传感器的动态校准研究

Dynamic calibration study of thin film heat flow sensor on curved structure

搭建了以高功率半导体激光器作为热流源的动态测试系统,响应时间为3.5μs,热流上限为50 MW/m2,可以产生阶跃、脉冲、变频正弦等动态激励信号。分别使用脉冲激励法和变频正弦激励法对传感器进行时域和频域的动态校准。时域上以脉冲信号作为激励信号,使用负阶跃测试法测量时间常数,用响应速率比表征热流传感器的动态响应特性;频域上以变频正弦信号作为激励信号,通过快速傅里叶变换绘制出频率特性曲线,得到传感器的频率响应为18.4 Hz。并对两种动态校准结果进行了分析。

A dynamic testing system with high-power semiconductor laser as heat flux source is built,with a response time of 3.5μs.The upper limit of heat flow is 50 MW/m2,which can generate dynamic excitation signals such as step,pulse,and variable frequency sine.Pulse excitation method and variable frequency sine excitation method are used respectively to dynamically calibrate the sensor in time and frequency domains.Pulse signals is used as excitation signals in the time domain,the negative step test method is used to measure the time constant,and the response rate ratio is used to characterize the dynamic response characteristics of the heat flow sensor.In the frequency domain,a variable frequency sine signal is used as the excitation signal,and a frequency characteristic curve is drawn through fast Fourier transform(FFT),resulting in frequency response of 18.4 Hz of the sensor.The two dynamic calibration results are analyzed.