Measuring flow velocity vector magnitude direction and sign - using various sensors on rotating shaft and speed matching

摘要

A rotating measurement device enables the magnitude, direction, and sign of a flow velocity vector to be measured without calibration. The previously used heated wire sensor can be replaced by a thermal, thermoelectrical,mechanical, or electromechanical sensor (17) having a greater mechanical resistance to flow effects. The sensor measures the speed about the axis of rotation (1) resulting from its rotation and the relative flow speed. The resulting signal reaches a min. when the flow speed is aligned with the perpendicular to the rotation axis. This is achieved by varying the sensor rotation velocity until the sensor peripheral velocity equals the flow velocity. The flow speed vector can then be accurately determined from the radius of rotation (R) the revolution rate, and the signal min. phase.