Uncertainty and calibration of wind anemometers
Wind direction and speed are an important component of natural climate, not only as a response to the characteristics of atmospheric circulation, but also as a parameter for climate comparisons between different places and as a source of energy. Observation of wind speed and direction, due to the use of wind anemometers and manual use of equipment, observation methods and measurement principles of the difference between the observed values between them is unavoidable. Then the size of this difference and the reason for the difference is worth exploring.
With the change of the times, the wind anemometer is developing rapidly new instruments in all walks of life in the country, especially the wind anemometer used to predict the national meteorological and marine is an important task, in order to make the reliability of the wind anemometer data measurements with traceability and quality assurance, it is necessary to carry out the instrument instrumentation of the machine calibration, especially in the dynamic conditions of the calibration measurements in the wind tunnel.
Wind wind anemometer uncertainty of the entire device wind speed relative to the standard uncertainty, should include the second-class standard Pitot static pressure tube and micromanometer composed of the uncertainty of the results of the standard instrument, the wind tunnel airflow instability and inhomogeneity caused by the uncertainty and uncertainty of the device.
Wind anemometer calibration method
(1) Appearance check qualified wind anemometer before the following calibration.
(2) Pitot tube and wind anemometer in the wind tunnel checker installation location and requirements: Pitot tube total pressure hole should be aligned with the direction of airflow, Pitot tube probe axis from the working section of the cave wall (25 ± 5) mm, Pitot tube should be installed vertically, firmly installed in the working section of the wind tunnel cave wall.
Wind anemometer in the application of the process of the protective layer should be strong, uniform, there shall be no delamination, obvious defects such as rust, etc., the installation of the part and the use of the instructions should be strictly in accordance with the requirements of the correct installation, so as not to cause an increase in the error of the data. The application of wind anemometer in agricultural production has an important role in the early prevention and protection of crops.
