In complex flow fields, the steady-state, three-dimensional attributes can be measured intrusively using a multi-hole pressure probe. These probes are built to be as small as possible to minimize flow disturbance, but the small size makes them susceptible to both manufacturing tolerances and fouling. As such, each probe must be calibrated on a regular basis and care must be taken to ensure that the geometry is not disturbed. The probes are operated in either “nulling” or “non-nulling” modes, the latter being the simpler of the two in terms of experimental setup and mechanical fixturing. This has made non-nulling mode the preferred choice for many years; however, non-nulling mode necessitates complete three-dimensional calibration data. Sector-based calibration strategies have become nearly universal, although improvement efforts continue. This paper presents a new calibration and data analysis strategy that gives shorter calibration times and more robust data reduction.
A novel calibration algorithm for five-hole pressure probe