Hybrid MPI/OpenMP parallelization of an Euler–Lagrange approach to cavitation modelling

An Euler–Lagrange approach is developed for numerical simulations of cavitating flows. Within this approach the Navier–Stokes equations are solved for the Eulerian liquid/vapor-mixture. Supplementary equations for the bubble size and motion are solved for each of the bubbles/nuclei, composing a discrete vapor phase. Such an approach is computationally demanding when computational grids with several Mio cells and many ten thousand bubbles are considered. The paper reports the development and verification of an efficient hybrid MPI/OpenMP algorithm for coupled Euler–Lagrange simulations. The proposed algorithm facilitates cavitation predictions for challenging industrial applications, such as cavitating marine propellers, in a reasonable amount of wall-clock time.