The average temperature of flow field can be measured,and the quantitative calculation of the temperature of flow field is calculated by using schlieren technology.The formula and principle of quantitative calculation for the flow field temperature are analyzed,and a set of transmission type schlieren measuring device is designed.The schlieren image analysis method is used to calibrate the temperature.In order to reduce the influence of the uneven gray scale level of the image caused by test environment changing to the measurement accuracy,the average gray scale value of a region in the image instead of the gray value of a point is selected for calibration curve.The temperature controllable heating metal plate is adopted as measuring object,and a series of different temperature points are selected,each group of the temperature points are simultaneously measured and recorded by adopting schlieren device and Pt100.The experimental results show that there is a good consistency between the temperature of the metal plate of the heating platform measured by schlieren device and Pt100. It is practicable to calculate the temperature quantitatively for the flow field by schlieren device.%纹影技术可以测量流场的平均温度,对流场温度作定量计算.分析了流场温度定量计算的公式和原理,设计了一套透射式纹影测量装置.采用纹影图像分析法对温度进行标定.为了减小试验环境变化引起的纹影图像灰度不均匀对测量精度的影响,取图像中某一区域的平均灰度值代替某一点的灰度值作标定曲线.采用温度可控加热金属板作为测量对象,选取一系列温度点,同时利用纹影仪和Pt100对每一组温度值进行测量和记录.试验结果表明,对于加热金属板表面温度,纹影仪测量的温度值和Pt100测量的温度值具有较好的一致性;利用纹影仪对流场温度进行定量计算是可行的方法.
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