NIST calibrates anemometers as a function of airspeed vector and turbulence intensity (Tu). The vector capability (sometimes called ‘3D’) is particularly important for calibrating multi-hole differential-pressure probes that are often used to quantify pollution emitted by smokestacks of coal-burning electric power plants. Starting with a conventional ‘1D’ wind tunnel, we achieved vector and Tu capabilities by installing translation/rotation stages and removable turbulence generators (grids or flags). The calibration ranges are: yaw angle 180; pitch angle 45; airspeed 1ms⁻¹ to 30ms⁻¹; turbulence intensity 0.07 ⩽ Tu ⩽ 0.25; average data collection rate: 300 points/h at fixed Tu. The system’s expanded uncertainties corresponding to 95% confidence level are: airspeed 0.0045 |V| + (0.036/|V|)² where |V| is the magnitude of the airspeed in m s⁻¹; pitch and yaw angles 0.3; and turbulence intensity 0.03 Tu. The airspeed working standard is a laser Doppler anemometer that is traced to SI unit of velocity via a spinning disk. Calibrations are corrected for blockage by the instrument under test and its supports.

NIST 将风速计校准为空速矢量和湍流强度 ( Tu ) 的函数。矢量功能（有时称为“3D”）对于校准多孔压差探头尤为重要，这些探头通常用于量化燃煤发电厂烟囱排放的污染物。从传统的“一维”风洞开始，我们通过安装平移/旋转阶段和可移动的湍流发生器（网格或旗帜）实现了矢量和Tu功能。标定范围为：偏航角180；俯仰角45；空速 1ms ^-1至 30ms ^-1；湍流强度 0.07  Tu  0.25；平均数据采集率：300 points/h at fixed Tu. 对应于 95% 置信水平的系统扩展不确定性为：空速 0.0045 | 五| + (0.036/| V |) ²其中 | 五| 是以 ms ⁻¹为单位的空速大小；俯仰角和偏航角 0.3；和湍流强度 0.03 Tu。空速工作标准是激光多普勒风速计，通过旋转圆盘追踪到 SI 速度单位。针对被测仪器及其支架的堵塞校正校准。