微风速标准装置的建立和热线风速仪校准方法的实验研究

摘要

中国计量科学研究院建立了微风速标准装置,基于该标准装置对热线风速仪的校准展开了实验研究.微风速标准装置基于相对法测量原理,实验通过气浮滑车搭载热线风速仪运动,由激光干涉仪测得的距离对时间微分得到标准速度,通过这种方式实现了热线风速仪的校准.滑车的运动速度可以溯源到国家计量院的时间和长度基准;此外,根据热线风速仪传感器的理论模型计算得到了热线风速仪的静态特性方程,比较理论模型与校准结果,发现二者具有良好的一致性.实验结果和不确定度分析表明:微风速标准装置的扩展不确定度U=0.82％(k=2);热线风速仪校准结果的扩展不确定度U=2.42％(k=2).%The low air speed reference facility is established at NIM of China,based on the device,the experiment on calibration of hot wire anemometer is investigated.The facility is described in detail and the calibration method for hot wire sensor is introduced.Based on the reciprocity principle,the sensor probe is mounted on the carriage that slides with consistent speed and the sliding stroke is measured by laser interferometer accurately during calibration process.The velocity measurement is therefore traceable to the measurement of length and time primary standards,additionally,the parameters of static equation is obtained according to theoretical module of hot wire sensor,the experimental results are consistent with theoretical equation.The experimental results and uncertainty analysis show that the expanded uncertainty of the breeze standard device is U =0.82％ (k =2),and the expanded uncertainty of calibration result of hot wire anemometer is U =2.42％ (k =2).