DNS of Droplet-Vortex Interaction with a Karman Vortex Street


Predicting fuel spray ínteraction with large scale structures still is a major challenge for state-of-the art CFD codes. In order to elucidate the mechansims involved, a fundamental study has been carried out in which the interaction of water droplets with a Karman vortex street is investigated.
The disperse two-phase flow around a cylinder has been computed taking into account the mass, momentum and heat transfer between both phases. Flow conditions are chosen such that large scale vortices are generated by periodic flow separations of the well known Karman vortex street. A homogeneous distribution of water droplets is injected into the hot air up-stream of the computational domain. The mixing process as well as the impact of the droplets on the gas phase instabilities is analyzed in the downstream region where large sclae vortex struxtures are present.