Dynamics of the nonequilibrium flow in a duct with obstruction

Abstract

This work aims to numerically simulate the dynamics of a channel flow with an obstruction since the moment we inject a fluid with an homogeneous velocity profile. The simulations uses the open source tools of the OpenFOAM platform, the pisoFoam and the LES turbulence model, describing in detail the velocity profiles of laminar and turbulent flows. We also perform a boundary layer mapping in the presence of an obstacle. We used three different domains to follow the evolution of the velocity profile while the fluid progresses downstream and passes the obstruction. The results reproduce the well-known results of laminar flow in a channel, as well as the average velocity profile in the turbulent regime and the occurrence of attachments by the obstruction. These preliminary results are used to validate the solvers and the mesh used. Next, an analysis of the velocity profile dynamics resulted in determining an exponential decay of the root mean square deviations of the homogeneous to the parabolic, and to the turbulent regime in the channel.