DOI: 10.1615/ICHMT.2015.THMT-15
ISBN Print: 978-1-56700-427-4
ISBN CD: 978-1-56700-428-8
Identification of material vortices
RESUMO
Our aim is to characterize the transport of passive scalars or particles by vortices. As an example we study the heat transfer from a heated plate due to an impinging turbulent jet in the high subsonic regime. Common vortex identification schemes rely on invariants of the velocity gradient tensor. They are Gallilean invariant but material derivatives which follow clusters of particles or patches of heat also involve time dependent rotations of the observing frame. Therfore we seek for objective criteria. One possibility is the vortex identification by Haller (2005). It was derived for incompressible flows and in this contribution we seek a relaxation of that constraint.