Numerical calibration of a conical five-hole probe for supersonic measurements

A miniature conical five-hole probe of 30° half-angle was numerically calibrated for measurements of flow properties at supersonic Mach numbers in order to circumvent the traditional experimental approach, vastly demanding on resources. The principle of a multi-hole conical probe is based on the notion that Mach number, pressure and directionality of the incoming stream may be correlated with the combination of pressure readings on the conical probe surface and a Pitot port situated at the flat tip. Using a three-dimensional thin layer Navier-Stokes solver, calibration data were generated for the range of Mach numbers and pitch angles of interest. The validity of the computed pressure distributions on the probe surface was subsequently confirmed in a series of wind tunnel tests including low Mach number and high angularity flow-field. The current study also demonstrated the profound influence of the blunt tip on the nearby static pressure ports, its relevance to the ultimate modelling strategy and the resulting calibration charts.