Reduced basis simulations as a tool for generating turbulent inlet-data for two opposing jets

Abstract

Reduced basis simulations are used in order to generate turbulent inlet boundary conditions for a direct numerical simulation of two opposing wall jets. The two entering jets are fully turbulent channel flows of Reynolds number 180, based on friction velocity and half channel height. The inflow turbulence is generated by solving dynamical equations for the large scales only, while less energetic small scales are added randomly. The proper orthogonal decomposition method is used to identify the large scale modes used in the basis set. Mean velocity and turbulence statistics have been reported in various planes of the interaction region and the outwash jet. The increase in maximum turbulence energy from the inlet jet to the stagnation region is about 500%. The spreading rate of the merged jet was found to be 0.125. Copyright © 2005 John Wiley & Sons, Ltd.