MEASUREMENT OF ROLLING MOMENT, LIFT AND DRAG ON A FLAPPED DELTA WING IN A HYPERSONIC SHOCK TUNNEL USING A FORCE BALANCE

摘要

A force balance to measure roll, lift and drag on aerodynamic models in short duration hypersonic test facilities, such as shock tunnels, has been developed and tested on a flapped delta wing model at a freestream Mach number of 8. The flow total enthalpy and freestream unit Reynolds number were 0.83 MJ/kg and 0.98 million, respectively. The balance structure has a soft suspension system that allows the model to have almost a free flight during the short duration aerodynamic test in the shock tunnel. The balance was mounted inside the hollow model and was equipped with acceleration-sensitive sensing elements (accelerometers) to sense the aerodynamic forces and the moment on the model. The measurements were carried out at different angles of incidence of the model. The acquired signals of the accelerometers were reduced to aerodynamic force and moment coefficients based on the theory of applied mechanics and aerodynamics. Also, the force and moment coefficients were theoretically deduced based on the Newtonian theory, which is an accepted analytical approach for hypersonic bodies. A good agreement has been observed between the experimental and the analytical results.