Mass and momentum transport in longitudinal vortical structures in liquid flow Example of Görtler vortices

Abstract

 The difference between mass and momentum transport in longitudinal vortical structures is shown in this paper. The patterns observed by visualization using laser induced fluorescence are the signature of the mass transport, while the flow structures revealed by anemometry show the momentum transport. Experiments and numerical simulations are performed in order to compare the velocity field of the Görtler instability with the mass distribution of a passive scalar. The typical scales involved in this problem are discussed with relation to the Schmidt number, in order to compare the size of the observed “mushrooms” with the size of the longitudinal Görtler vortices. It is found that the nonlinearities which strongly influence the velocity perturbation do not modify the shape and the size of the scalar structures.