Calibration of the Preston probe for high Reynolds number flows

Experiments were performed in order to calibrate Preston probes for high Re ynolds number applications. The results extend previous calibrations to Rey nolds numbers that are approximately 30 times larger. The new calibration i s valid in the range 6.4 < x* < 11.3, that is, 4.3 < y* <less than> 8.7 and 280 < D+ < 45 000. Within this range, the wall shear stress may be found t o within better than +/-0.8%, as long as inner layer scaling applies up to a wall distance equal to the probe diameter.