On the use of a linear interpolation method in the measurement procedure of a seven-hole pressure probe

Abstract

Calibration and measurement procedures implemented to work with a seven-hole directional pressure probe in the mapping of pressure and velocity wind tunnel flows are reported in this paper. The performances of two different methods used to derive the flow characteristics (direction and magnitude of flow velocity vector and total and dynamic pressure) from the seven pressure values measured by the probe, are comparatively evaluated. The conventional method, based upon the fitting of the calibration directional data with fourth order polynomial functions is compared with a new method where direct linear interpolation is performed over the calibration matrices. Besides the comparison of the two methods, the fundamentals of the working procedure of the probe are briefly explained and an example of the mapping of the flow field around a wing model in a wind tunnel experiment is presented.