Implicit LES Predictions of the Cavitating Flow on a Propeller

Abstract

We describe an approach to simulate dynamic cavitation behavior based on large eddy simulation of the governing flow, using an implicit approach for the subgrid terms together with a wall model and a single fluid, two-phase mixture description of the cavitation combined with a finite rate mass transfer model. The pressure-velocity coupling is handled using a PISO algorithm with a modified pressure equation for improved stability when the mass transfer terms are active. The computational model is first applied to a propeller flow in homogeneous inflow in both wetted and cavitating conditions and then tested in an artificial wake condition yielding a dynamic cavitation behavior. Although the predicted cavity extent shows discrepancy with the experimental data, the most important cavitation mechanisms are present in the simulation, including internal jets and leading edge desinence. Based on the ability of the model to predict these mechanisms, we believe that numerical assessment of the risk of cavitation nuisance, such as erosion or noise, is tangible in the near future.

Investigation of Cavitation Models for Steady and Unsteady Cavitating Flow Simulation

“…Therefore, a systematic research on this topic is necessary. Recently, Large Eddy Simulation (LES) has been studied for unsteady cavitation simulations by a few researchers [35][36][37]. Some promising results have been obtained for some geometrically simplified cases.…”

Cloud Cavitating Flow That Surrounds a Vertical Hydrofoil Near the Free Surface

“…Cavitating flow is often examined through a water tunnel [3] or water tank test [4]. Computational fluid dynamics (CFD), which has been integrated into commercial software FLUENT and CFX [5][6][7] as well as into open-source [8][9][10][11] and in-house [12][13][14][15][16] software, has been recently introduced as a major approach for investigating cavitation. The cavitating flow of the unsteady cloud around the foil [17][18][19], propeller models [20], and other underwater vehicles [7,21] presents typical problems.…”

Effect of mesh resolution on large eddy simulation of cloud cavitating flow around a three dimensional twisted hydrofoil

“…LES method is expected to give better predictions of larger-scale turbulent eddies with better accuracy with some promising results already obtained. For example, an implicit LES method was used to simulate dynamic cavitation behavior of a propeller by Bensow et al [20] and Lu et al [21]. LES with the WALE SGS stress model was adopted to calculate the cavitation shedding and horse-shoe structures by Ji et al [22][23][24] and Huang et al [25].…”