Numerical study of cavitating flow in asymmetrical nozzles of injectors/atomizers. application to fully developed cavitation cases II

Abstract

In the first part of this work a broad discussion related to steady and unsteady state cavitation cases and the calibration of turbulence models in steady state cases simulations was presented. In this second part, a numerical analysis of the unsteady flow behavior in nozzles of injectors/atomizers is presented. Previous works showed that it is possible to capture several of the incipient cavitating flow characteristics performing a careful calibration of the Eddy Viscosity Models in nozzles. This work extends the numerical study for these nozzles in cases where the fully developed cavitation state appears. Again, a careful calibration of the selected Eddy Viscosity Models becomes an important task to obtain accurate predictions of the flow. The results obtained show that it is possible to capture the main cavity features and the characteristic frequencies of the flow unsteadiness. The obtained conclusions could be useful to improve injectors design using numerical modeling, because the detection of the typical frequencies related to the flow unsteadiness could be useful to detect possible coupling between some of these frequencies and one of the natural vibration modes of the nozzle leading to a possible undesired fluid- structure interaction.