CFD ANALYSIS ON JET NOISE REDUCTION USING FAN FLOW DEFLECTORS

Abstract: Fan flow deflection for jet noise reduction was applied to subscale nozzles simulating the geometry and exhaust conditions of separate-flow turbofan engines. Two types of deflectors were investigated, one comprising two pairs of vanes internal to the fan duct and the other consisting of a wedge positioned outside the fan duct. The noise reduction achieved by the vanes was strong in the downward direction and moderate in the sideline direction. The wedge generated significant attenuation in both directions. Here the vane deflector going to be used on fan duct. When the flow passes through the nozzle the turbulent eddies can be generated more. While place a vane deflector on the fan duct, the vane deflectors reduce the TKE on the underside of the jet and increase it on the topside of the jet. There is a significant correlation between the decrease of the TKE near the end of the potential core and the reduction in overall sound pressure level in the direction of peak emission and the flow becomes streamlined flow and then the noise can be decreased.