基于脉冲热流激励的戈登式热流传感器动态测试

Dynamic Test of Gardon Heat Flux Sensor Based on Pulse Heat Flux Excitation

由于薄膜热流传感器耐温上限高、体积小且响应速度快,传统方法无法满足其动态测试需求,因此提出了一种以激光器为热源的动态测试方法,该方法具有功耗低、响应速度快以及能够提供高热流等优点。设计搭建了基于高功率光纤输出半导体激光器的热流传感器动态测试系统,主要由激光器、微透镜光斑均匀化系统、热流传感器和数据采集系统组成。为了研究在不同脉冲宽度条件下传感器的时间常数的变化,选用了具有能够直接测量辐射热流、吸收全光谱范围的能量以及响应时间短等优点的戈登式热流传感器(Gardon计)对热流传感器动态测试系统进行了测试。利用系统完成了GD-B4-200K型Gardon计在脉冲热流激励信号下的动态测试,分析了5 ms、10 ms、15 ms、20 ms和30 ms脉冲宽度条件下传感器的时间常数的变化。最终得出在脉冲激励下,脉冲激励信号的脉冲宽度应小于传感器时间常数一个数量级的结论,因此需要对脉冲宽度进行严格精确的控制。未来,系统可有效解决航空、航天等诸多领域内的高速辐射热流传感器动态测试问题。

Due to the high temperature limit, small volume and fast response speed of thin-film heat flux sensor, traditional methods can’t meet its dynamic testing requirements.Therefore, a dynamic test method using laser as heat source is proposed, which has the advantages of low power consumption, fast response speed and high heat flux.The dynamic test system of heat flux sensor based on high power fiber output semiconductor laser is studied and built, which is mainly composed of laser, micro lens spot homogenization system, heat flux sensor and data acquisition system.In order to study the change of the time constant of the sensor under different pulse widths, the Gardon heat flux sensor, which has the advantages of direct measurement of radiant heat flux, absorption of energy in the full spectral range and short response time, is selected to test the dynamic test system of the heat flux sensor.The dynamic test of GD-B4-200K heat flux sensor under pulse heat flux excitation signal is completed by using the system, and the change of the time constant of the sensor under different pulse widths of 5 ms, 10 ms, 15 ms, 20 ms and 30 ms are analyzed.Finally, it is concluded that under pulse excitation, the pulse width of pulse excitation signal should be less than one order of magnitude of sensor time constant, so it is necessary to strictly and accurately control the pulse width.In the future, the system can effectively solve the dynamic testing problems of high-speed radiative heat flux sensors in many fields such as aviation and aerospace.