Chenyang Weng

The attenuation of sound by turbulence in internal flows

The attenuation of sound waves due to interaction with low Mach number turbulent boundary layers in internal flows (channel or pipe flow) is examined. Dynamic equations for the turbulent Reynolds stress on the sound wave are derived, and the analytical solution to the equation provides a frequency dependent eddy viscosity model. This model is used to predict the attenuation of sound propagating in fully developed turbulent pipe flow. The predictions are shown to compare well with the experimental data. The proposed dynamic equation shows that the turbulence behaves like a viscoelastic fluid in the interaction process, and that the ratio of turbulent relaxation time near the wall and the sound wave period is the parameter that controls the characteristics of the attenuation induced by the turbulent flow.

Sound-turbulence interaction in low Mach number duct flow

When sound waves propagate in ducts with the presence of turbulent flow, turbulent stresses can cause extra attenuation of the wave in addition to that caused by viscothermal effects. Different mod ...

A Linearized Navier-Stokes Method Including Turbulence Damping

In this paper, a method for including damping of acoustic energy in regions of strong turbulence is derived for a linearized Navier-Stokes method in the frequency domain. The result is applied in a ...