On the Importance of Turbulence Modelling of the Flow after a 90 Pipe Bend
(English)Manuscript (preprint) (Other academic)
The flow in a free jet after a 90 pipe bend has been investigated by Large Eddy Simulations (LES) and Reynolds Averaged Navier-Stokes (RANS) simulations. The numerical results for the mean velocity profiles, flow fields, and power spectral densities have been compared to experimental data. The results show that LES has been able to predict the mean components of the velocity field and in resolving dynamic motions such as vortex switching. LES without an explicit SGS model (termed as ILES in the following) has been found to work well with flows of this type as long as the grid resolution is sufficiently fine. Different Sub-Grid-Scale (SGS) models have also been used. LES with different SGS models result in very similar results when a fine enough grid is used. The ILES approach also gives reasonably accurate results for the mean values even for coarser grids.
Fluid Mechanics and Acoustics
Research subject Engineering Mechanics
IdentifiersURN: urn:nbn:se:kth:diva-151395OAI: oai:DiVA.org:kth-151395DiVA: diva2:748452
QS 20142014-09-192014-09-192014-09-19Bibliographically approved