Analysis and Control of Weapon Bay Flows

Numerical analysis of the flow in weapon bays modelled as open rectangular cavities of length-to-depth (L/D) ratio of 5 and width-to-depth (W/D) ratio of 1 with doors-on and doors-off is presented. Flow conditions correspond to a Mach and Reynolds numbers (based on cavity length) of 0.85 and 6.783 million respectively. Results from Unsteady Reynolds-Averaged Navier-Stokes (URANS), Large-Eddy Simulation (LES) and Detached-Eddy Simulation (DES) are compared with the simulation methods demonstrating the best prediction of the complex flow. Results for a non-clean cavity (without doors) with a rear wall sting-mounted store are then presented to illustrate the effect of the missile on the cavity flow-field. The final part of the paper then demonstrates flow control of the cavity using passive control devices including the spoiler, slanted cavity walls and steady jet blowing with the jet proving to be the most effective in mitigating the noise level and frequency content inside the cavity.