Prediction of the flow-induced noise for practical applications using the SNGR method

In this paper an engineering method for the prediction of noise generated by a turbulent flow is presented. The presented approach is based on the assumption that the acoustic phenomena do not provide feedback to the turbulence. Thus, parameters such as the turbulent kinetic energy and the integral length scale can be obtained from Reynolds Averaged Navier Stokes (RANS) simulations. Subsequently an SNGR approach is employed for generating an unsteady turbulent velocity distribution that possesses these turbulent characteristic values. Since the propagation of sound is little influenced by turbulent and viscous effects it can be described by the Euler equations. These Euler equations are solved on an unstructured grid, allowing for arbitrarily complex geometries. Results of simulations employing this Computational Aero Acoustics approach for several applications are compared with measurements, showing good agreement