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Our customer is a global corporate R&D group that supports futuristic aircraft development programmes through cutting edge technology inputs. Recent laws pertaining to noise pollution demands aircrafts to cut noise by 1/3rd during take-off and approach near populated areas. In such situations, the major contributor of noise is deflected flaps of high-lift wing configuration. Since, aerodynamic lift and farfield noise are closely related to each other, multi-disciplinary optimization is needed to minimize noise while maintaining aerodynamic performance.
Zeus Numerix developed a coupled CFD-CAA optimization workflow on Kepler framework using its proprietary analysis tools. CFD simulation generates unsteady pressure field around the wing, which is transformed into Dipole / Monopole acoustic sources. An FWH based acoustics solver generates directivity plot of farfield noise. This simulation framework is coupled with automated structured mesh generator and GA optimizer to allow automated aero-acoustics assessment of candidate wing designs.
Through the project partner CDAC, customer was delivered the integrated optimization framework on a grid computing resource. For the given free-stream condition, the framework identified the optimum flap & orientation. Down from the original noise level of 72.1dB, optimized configuration generated noise level of 68.7dB i.e. a reduction of 32.3%.