Development of functional relationships for air-data estimation using numerical simulations

Flush Air-Data Sensing (FADS) systems use an array of surface pressure measurements to infer the speed, position, and orientation of a vehicle in flight. The non-intrusive nature of such systems make them especially useful for hypersonic vehicles. Determining the functional relationship between measured surface pressure and the airdata of interest (e.g. Mach number, angle-of-attack, etc.) is the first step in implementing a FADS system. In this work, these functional relationships are developed by fitting surfaces/curves to a set of numerical simulations. In the absence of ground or flight test data, the resulting FADS algorithm is tested with a second set of numerical simulations. The largest error in predicted Mach number is ±0.2, in angle-of-attack is ±0.05°, in angle-of-sideslip is ±0.15°, and in freestream pressures is ±20 Pa