Hot Film Calibration System Using a Free Jet in Water (original) (raw)

HWA (hot wire anemometry) is a very important tool for fluid mechanics research, and even today several industrial, aeronautical, automobile and military applications have been found for this thermal anemometer, substituting with advantages a number of traditional flow measurement ways like orifice plates and Pitot tube. Despite the several advantages of HWA, frequent necessity of probe calibration remains the greatest difficulty in using this type of anemometer. A device for film probe calibration in water mwdium for low velocities has been proposed in the present work. This calibration apparatus produces a free jet with moderates Reynolds numbers (up to 10 4) and the probe is inserted into the root jet, permitting the calibration process. Several visualized images of the free jet has been captured using different flow visualization technique and several measurements of the velocity profile and turbulence is obtained. The proposed apparatus shows a good optation in an accurated and...