Calculation of support interferences on the aerodynamic coefficients for a windtunnel calibration model

Summary An AGARD calibration model has been tested in the subsonic cryogenic windtunnel (KKK) of DLR Köln, model support interferences are calculated in the form of corrections to the aerodynamic coefficients. Two different model support systems are investigated: the model mounted on a horizontal sting (rear sting), and the model mounted on a vertical sting (ventral sting). Since for these configurations earlier experiments already exist, the corrections obtained are applied to these measurements for further verification. Furthermore the sting influences on the longitudinal static stability of the model are investigated in more detail. A 3D-panel method is used which allows simultaneous calculation of several displacing and lifting bodies of nearly arbitrary shapes in the flow. The aerodynamic coefficients are obtained by numerical integration of the surface pressure distribution on the model.