A Numerical Study of Pulsed Turbulent Pipe Flow

Abstract

A numerical study of fully developed turbulent pipe flow due to a sinusoidally varying (with respect to time) axial pressure gradient was carried out using a nonlinear three-dimensional model. Pseudospectral methods were used to solve the model equations. The pulsation frequency was characteristic of the wall region eddies in steady turbulent flow. Attention was focused on the viscous wall region, and it was found that the mean profiles of axial velocity, fluctuation intensities, and turbulence production rate were essentially the same as in steady flow. The fluctuation intensities and the turbulence production rate showed a definite phase relationship to the pressure gradient. The turbulence production rate was the largest at the time in the pulsation cycle at which the largest adverse pressure gradient existed.