Miniature Four Hole Probe for Three Dimensional Boundary Layer Measurements

Abstract

The design, fabrication and calibration details of a miniature four hole probe for three-dimensional boundary layer measurements are presented in this paper. The probe has a nominal measuring area of 1 mm2 and has a nominal dimension of 0.4 mm in the boundary layer direction thus minimizing pressure and velocity gradient errors and wall vicinity errors. The probe is calibrated in an open jet calibration tunnel at a velocity of 50 m/s in the yaw and pitch angle range of + 40O at 5O interval. The calibration coefficients are defined, calculated and presented. The sensitivity of the calibration coefficients is also calculated and presented.

Look Up Table Method for Five Hole Probe Data Reduction

“…Although the look up table method is developed for use with a five hole probe with the calibration done at equal ranges in both yaw and pitch planes, the method is successfully applied for data reduction of a four hole probe with the calibration done at unequal ranges in yaw and pitch planes [8] and an ultra miniature three dimensional wake probe [9].…”