This proposal outlines a plan for developing new technology to provide accurate real-time noise prediction for rotorcraft in steady and maneuvering flight. Main rotor and tail rotor thickness and loading noise, including Blade-Vortex Interaction noise and Tail-Rotor Interaction noise, will be predicted with physics-based methods by enhancing a real-time lifting surface/free-vortex-wake blade aerodynamics module and coupling it to maneuvering flight acoustic prediction software modified for operation in a time-marching flight simulation environment. Also included will be methods to account for spherical spreading, atmospheric absorption, and ground effect for flat level terrain. All new software will be designed with the eventual goal of supporting both high fidelity and real-time solutions through a hierarchy of methods. Phase I will provide the development of proof of concept prototype software demonstrated for both steady and maneuvering flight. Phase I will also see an evaluation of real-time potential of the various models. Phase II will provide the development of a fully-functional, noise prediction software module with real-time and high fidelity capability designed for easy coupling with flight simulation software. Phase II will also see additional enhancements in the areas of acoustic propagation, High Speed Impulsive noise, and engine and transmission noise.
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