Turbulence in the direction of the average speed

The component of turbulence in the direction of speed Vulcan be measured with a sensor perpendicular to the average speed. In the analog

anemometers, the corresponding voltage was measured with an rms voltmeter, based on the Joule effect, from the signal filtered to remove the DC component. In the modern computerized anemometers, the rms voltage value is obtained from

To obtain the rms value of velocity in linearized systems a factor of proportionality is simply applied. In non-linearized systems, conversion is accomplished by determining the slope of the calibration curve at the point of measurement. If the turbulence is large, an error of distortion is introduced in this way due to the uncertainty in choosing the proper curve slope.