Effects of compression on coherent structures in an enclosure
(English)Manuscript (preprint) (Other academic)
The effects of compression on turbulent swirling flows are studied using Large-Eddy Simulations (LES). In this study, the geometry investigated is a cylinder with swirling motions of dierent strengths with superimposed isotropic turbulence. During compression the evolution of turbulence and vorticity is investigated. During early compression, rapid diusion of turbulence is found. In the later part of the compression an increase of turbulence and vorticity is observed and linked to vorticity-dilatation interaction. It is shown that the swirling motion suppresses turbulence and turbulent anisotropy. The longitudinal integral length scale of the tangential fluctuations is found to be approximately twice the transverse length scale. The longitudinal length scale is largely unaffected by compression whereas an effect on the transverse length scale is observed.
Fluid Mechanics and Acoustics
IdentifiersURN: urn:nbn:se:kth:diva-124235OAI: oai:DiVA.org:kth-124235DiVA: diva2:633839
FunderSwedish Energy Agency
QS 20132013-06-272013-06-272015-04-20Bibliographically approved