Numerical Study of Unsteady Cavitating Flows around a Hydrofoil

In this paper, we report the results of a numerical investigation on unsteady cavitating flows around a circular leading edge (CLE) hydrofoil. The objective of this study is to properly predict the appearance of cavitation pocket, its development and its detachment causing adverse effects on industrial systems such as microscopic plastic deformations at the solid walls. For this reason it is very important to study the influence of turbulence models on simulation results. We present a closing of the hydrodynamic equation system by a transport equation of an active scalar (volume fraction of the vapor phase) with a source terms. The Computational Fluid Dynamics (CFD) code used is ANSYS CFX. Before comparing the capability of the different turbulent models to predict unsteady behavior of cavitating flow along the hydrofoil, the study of the influence of the mesh resolution was performed in cavitating condition. This investigation was performed, on CLE hydrofoil, by monitoring the influence of for progressively finer meshes on the values of the drag CD and lift CL coefficients. Moreover, a study of the influence of the normal dimensionless distance to the wall (y+) was carried out on the hydrofoil surface. For the unsteady flow, a comparison of different turbulence models with the experiment leads to study the interaction of these models with the vapor pocket (detachment and collapse of vapor pocket). Two turbulence models were tested in this study: modified k-ε model and large eddy simulation (LES). In the present work, the predictions of velocity and pressure evolutions in the vicinity of the hydrofoil are compared to experimental data.

[1]  S. Khelladi,et al.  Experimental study of aerated cavitation in a horizontal venturi nozzle , 2016 .

[2]  Weixing Yuan,et al.  Modeling and computation of unsteady cavitation flows in injection nozzles , 2001 .

[3]  Eric Goncalves,et al.  EXPERIMENTS AND MODELLING OF CAVITATING FLOWS IN VENTURI: ATTACHED SHEET CAVITATION , 2010 .

[4]  M. Sarker,et al.  Numerical Prediction of Unsteady Behavior of Cavitating Flow on Hydrofoils using Bubble Dynamics Cavitation Model , 2016 .

[5]  R. Bensow,et al.  Implicit LES Predictions of the Cavitating Flow on a Propeller , 2010 .

[6]  Bin Ji,et al.  Numerical Simulation of Cavity Shedding from a Three-Dimensional Twisted Hydrofoil and Induced Pressure Fluctuation by Large-Eddy Simulation , 2012 .

[8]  Vineet Ahuja,et al.  Simulations of cavitating flows using hybrid unstructured meshes , 2001 .

[9]  Kevin P. Galvin,et al.  Bubble nucleation from gas cavities — a review , 1999 .

[10]  Olivier Coutier-Delgosha,et al.  Numerical modelling of cavitation erosion , 2009 .

[11]  E. Shirani,et al.  MODELING AND SIMULATION OF INTERFACIAL TURBULENT FLOWS , 2011 .

[12]  Wei Shyy,et al.  Evaluations of Cavitation Models for Navier-Stokes Computations , 2002 .

[13]  Roger E. A. Arndt,et al.  Instability of Partial Cavitation: A Numerical/Experimental Approach , 2000 .

[14]  Y. L. Young,et al.  Combined Experimental and Computational Investigation of Unsteady Structure of Sheet/Cloud Cavitation , 2013 .

[15]  L. Fuchs,et al.  Numerical investigation of throttle flow under cavitating conditions , 2015 .

[16]  J. Sauer,et al.  Physical and numerical modeling of unsteady cavitation dynamics , 2001 .

[17]  M. Farhat,et al.  Mind the gap: a new insight into the tip leakage vortex using stereo-PIV , 2014 .

[18]  Jean-Luc Reboud,et al.  TWO-PHASE FLOW STRUCTURE OF CAVITATION : EXPERIMENT AND MODELLING OF UNSTEADY EFFECTS , 1998 .

[19]  S. Frankel,et al.  Large Eddy Simulation of Turbulent-Cavitation Interactions in a Venturi Nozzle , 2010 .

[20]  Hatem Kanfoudi,et al.  A numerical Model to simulate the cavitating flows , 2011, Int. J. Model. Simul. Sci. Comput..

[21]  G. E. Reisman,et al.  Observations of shock waves in cloud cavitation , 1998, Journal of Fluid Mechanics.

[22]  E. Goncalvès,et al.  Modelling for isothermal cavitation with a four-equation model , 2014 .

[23]  Eric Goncalves,et al.  Numerical study of unsteady turbulent cavitating flows , 2011 .

[24]  Philippe Dupont.  Etude de la dynamique d'une poche de cavitation partielle en vue de la prédiction de l'érosion dans les turbomachines hydrauliques , 1993 .

[26]  Wei Zhang,et al.  Validation of dynamic cavitation model for unsteady cavitating flow on NACA66 , 2014 .

[27]  K. Hanjalic,et al.  High-speed visualization and PIV measurements of cavitating flows around a semi-circular leading-edge flat plate and NACA0015 hydrofoil , 2014 .

[28]  Youcef Aït Bouziad.  Physical modelling of leading edge cavitation , 2005 .

[29]  J. Carlton,et al.  Cavitation , 2019, Marine Propellers and Propulsion.

[30]  Christopher J. Rutland,et al.  A Numerical Study of Cavitating Flow Through Various Nozzle Shapes , 1997 .

[31]  Ehsan Roohi,et al.  Numerical Simulation of Cavitation around a Two-Dimensional Hydrofoil Using VOF Method and LES Turbulence Model , 2013 .

[32]  A. K. Singhal,et al.  Mathematical Basis and Validation of the Full Cavitation Model , 2002 .

[33]  J. Reboud,et al.  Two-phase flow structure of sheet cavitation , 1997 .

[34]  Q. X. Wang,et al.  University of Birmingham Experimental study on bubble dynamics subject to buoyancy , 2015 .

[35]  Yoshinobu Tsujimoto,et al.  Experimental Study and Numerical Simulation of Cavity Oscillation in a Conical Diffuser , 2010 .

[36]  Raynald Simoneau,et al.  On line measurement of cavitations erosion rate on a 2D NACA profile , 1989 .

[37]  B. Launder,et al.  The numerical computation of turbulent flows , 1990 .

[38]  Habib Hakimzadeh,et al.  Numerical Modeling of 2-D and 3-D Flows using Artificial Compressibility Method and Collocated Mesh , 2016 .

[39]  Robert F. Kunz,et al.  A preconditioned navier-stokes method for two-phase flows with application to Cavitation prediction , 1999 .

[40]  J. Reboud,et al.  Experimental and Numerical Studies in a Centrifugal Pump With Two-Dimensional Curved Blades in Cavitating Condition , 2003 .

[41]  T. Lili,et al.  A Reynolds Stress Closure for Compressible Turbulent Flow , 2011 .

[42]  Brane Širok,et al.  Development of a cavitation erosion model , 2006 .

[43]  Stephen D. Heister,et al.  Two-phase modeling of cavitated flows , 1995 .

[44]  Xiaocui Wu,et al.  Study of Characteristics of Cloud Cavity Around Axisymmetric Projectile by Large Eddy Simulation , 2014 .

[45]  Ying Chen,et al.  A Homogenous-Equilibrium-Model Based Numerical Code for Cavitation Flows and Evaluation by Computation Cases , 2008 .