United States Air Force Academy Air Force Academy United States
A current area of interest in the aeronautical community is the simulation of flow over an airborne turret. The research presented in this paper concerns the computational simulation of the flow over an airborne turret that was performed incorporating computational fluid dynamics CFD with optical beam post processing. The turbulence model used in the Cobalt CFD solver was the Delayed-Detached Eddy Simulation with Shear Stress Transport DDES-SST model. The CFD simulation matched flight conditions at an altitude of 15,000 feet and a Mach number of 0.4. The grid surrounding the turret contained 164M elements. After computing the flow field, the aero optical data reduction yielded the optical wave front distortions as the beam traversed the turrets wake. The ultimate goal is to use these modeling techniques to provide data to mitigate aberrations in the wave front resulting from the beam propagating through the flow field surrounding the airborne turret. The DDES-SST turbulence model provided an adequate model of a turrets wake for the given grid and aero-optic analysis techniques were used to determine the beam quality as it passes through the separated shear layer and the farfield irradiance.