Using RANS Calculations of Turbulent Kinetic Energy to Provide Two Point Flow Velocity Correlations and Surface Pressure Spectra.

摘要

This report gives the results of a study that used the linearized Navier Stokes equations to model spectra in turbulent flows. The first part of the study considers two dimensional wakes and provides estimates of two point correlation functions and spectra from the distribution of turbulent kinetic energy in the flow. In the second part of the study a turbulent boundary layer in the vicinity of a forward facing step is analyzed and results are given for the velocity and surface pressure spectra. Results are also given for the Green's function and the sound radiation efficiency from turbulence close to a forward facing step All results are compared with measurements obtained in a companion study at Virginia Tech.