| Popis: |
This work presents an experimental and numerical investigation of a confined turbulent flow behavior across a conical diffuser (2α = 16°). The role of a perturbation caused by the presence of an elbow in the test-section, upstream of the progressive enlargement, was studied. The main measurements were the static pressure, and the instantaneous velocity fields using the Particle Image Velocimetry (PIV). Post-processing of these PIV measurements were adopted using the Γ2 criterion for the vortices detection, and the Proper Orthogonal Decomposition (POD) technique to extract the most energetic modes contained in the turbulent flow and to the turbulent flow filtering. A data base has been also constituted, and was used to test the validity of the most models of turbulence, and in particular, a variant of the SST model.Copyright © 2009 by ASME |
