Aft-sting mount is the most common method of mounting wind tunnel models when performing aerodynamic (balance) measurements in wind tunnels, especially when testing missile configurations. The influence of this type of mount on the base pressure and drag characteristic has been widely investigated in the past, both by wind tunnel testing and Computational Fluid Dynamics (CFD). However, its influence on the longitudinal stability of the tested configuration has been poorly addressed.
Another aspect of great interest regarding the aft-sting mount is its effect on the flow characteristics in the near wake of the body. Several studies have shown that the presence of an aft-sting mount could significantly modify the shear layer characteristics (e.g., the reattachment point, velocity fluctuation frequencies etc.).
This work presents a comprehensive investigation of these two topics. Subsonic and transonic wind tunnel tests have been conducted with various sting to body diameter ratios, clearly showing the aft-sting’s effect on the tail aero-surfaces contribution to the longitudinal stability. Furthermore, hot-wire anemometer has been used in subsonic flow conditions for mapping the near wake flow field modifications in the presence of the aft-sting. These measurements demonstrate the damping effect of the aft-sting mount on the shear layer velocity fluctuations.
