A novel single-fluid cavitation model with gas content and slip velocity, applied to cavitating tip leakage vortex

Artikel i vetenskaplig tidskrift, 2023

In this paper, we develop a new model based on the single-fluid approach which consider the effects of gas content and slip velocity between the gas/vapor phase and the liquid phase in cavitation modeling. The derivation of the mathematical formulation of the model is presented in the context of Large Eddy Simulation (LES), although a similar derivation can be developed for a Reynolds-averaged Navier–Stokes (RANS) framework. To validate the model and to study the effect of including this physics, a cavitating Tip Leakage Vortex (TLV) formed around the NACA0009 foil is simulated. The results of the simulation are compared with the available experimental data and the results obtained from a conventional single-fluid approach. This comparison shows that the new model predicts cavitation regions in significantly better agreement with the experimental data, compared to the conventional single-fluid approach. This better agreement is observed for both the cavitation regions in the TLV and the cavitation regions at the leading edge. Analyzing the results, the reason for this significant improvement is shown to be the accumulation of non-dissolved gas due to the consideration of the slip velocity, and the effect of this accumulation in the cavitation formation. Furthermore, the effects of gas content and the size of nuclei in the incoming flow to the TLV are investigated, and these effects are discussed in detail.