A Four Hole Pressure Probe for Fluid Flow Measurements in Three Dimensions

Abstract

A pressure probe which facilitates measurement of mean flow quantities in three dimensions simultaneously is described. Its main feature is a tip shaped like the frustrum of a pyramid, with three-side holes equispaced around a central hole. Flow quantities are related to the hole pressures by calibration, so that the tedious procedure of nulling or pressure balancing can be avoided. The advantages of this configuration over five-hole probes are that a simpler probe with a smaller head results, fewer pressures need to be recorded and because no redundant information is collected, determination of the dependent flow quantities is simpler and unambiguous.