NUMERICAL INVESTIGATION OF ROD-AIRFOIL CONFIGURATION AEROACOUSTIC CHARACTERISTICS USING FFOWCS-WILLIAMS-HAWKINGS EQUATIONS

A Comparison of Ffowcs Williams-hawkings Solvers for Airframe Noise Applications

Aerodynamic Noise Prediction for a Rod-Airfoil Configuration using Large Eddy Simulations

Aerodynamic noise produced by aerodynamic interaction between a cylinder (rod) and an airfoil in tandem arrangement is investigated using large eddy simulations. Wake from the rod convects with the flow, impinges of the airfoil to produce unsteady force which acts as a sound source. This rod-airfoil interaction problem is a model problem for noise generation due to inflow or upstream-generated ...

AIAA 99-0231 Simulation of Acoustic Scattering from a Trailing Edge

Three model problems were examined to assess the diiculties involved in using a hybrid scheme coupling ow computation with the the Ffowcs Williams and Hawkings equation to predict noise generated by v ortices passing over a sharp edge. The results indicate that the Ffowcs Williams and Hawkings equation correctly propagates the acoustic signals when provided with accurate ow information on the i...

Numerical Investigation of S822 Wind Turbine Airfoil

We carried out direct numerical simulations of the flow past a two-dimensional S822 wind turbine blade section at a chord Reynolds number of Re=100,000 and an angle of attack of α = 5deg. Without blade rotation the separated boundary layer “rolls up” into spanwise vortices which then “break up” into smaller scale structures leading to transition to turbulence. Simulation results compare favorab...

Discrete Noise Prediction of Variable Pitch Cross-Flow Fans by Unsteady Navier-Stokes Computations

The unsteady viscous flow fields of a cross-flow fan are computed by time-accurately solving the two-dimensional incompressible Navier-Stokes equations with the unstructured triangular mesh solver algorithms. Based on pressure fluctuation data acquired at the surfaces of 35 rotating blades and stabilizer, acoustic pressures are predicted by the Ffowcs Williams-Hawkings equation. The aerodynamic...