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An experimental investigation is conducted in a high speed wind tunnel to suppress acoustic resonance. Conventional leading edge mass blowing actuator are used to disturb cavity flow. Detailed static-pressure and fluctuating-pressure measurements are obtained on the cavity walls to determine the effects on cavity flow characteristics. Wind tunnel test based analysis of the suppression of dynamic loads on the walls of a complex weapon bay using leading edge mass blowing is presented. The unique aspect of the concepts discussed here is the very low mass flow rates used to achieve significant suppression. The simulation results are used to gain insight into the mechanism governing the effectiveness of these jets. The PRTB are applied to a deep (L/D = 4. 5) cavity at transonic conditions of Mach 0. 8. The experimental results show excellent agreement with experiments showing an overall reduction of the noise levels of the order of 5 dBs with the control concepts. The primary mechanism of reduction is the break-up of the spanwise coherence in the shear layer into smaller vortical structures thus reducing the shear layer flapping and leading to a smaller imprint on the wall pressures. [ABSTRACT FROM AUTHOR]

The method based on overset unstructured grid technique is developed for the simulation of cavity flows and store separation. The numerical simulation for typical cavity flows and separation trajectory of WPFS model have achieved good agreement with experimental data and shown a promising capability for applications. The numerical simulation of door operation and store separation trajectory has been made to investigate the unsteady effects on aerodynamic characteristics of the door flap. It is found that under certain conditions, the door's movement has a strong effect on aerodynamic characteristics of the door flap, which must be seriously considered during the door flap and control system design procedure. Under current conditions, all the store separation procedure is safe. The present research provides a technical support for door flap design and store separation evaluation. [ABSTRACT FROM AUTHOR]