A study for cavitating flow analysis using DES model. (15th July 2018)

• Record Type: Journal Article
• Authors: Usta, Onur; Korkut, Emin
• Is Part Of: Ocean engineering. Volume 160(2018)
• Page Start: 397
• Page End: 411
• Publication Date: 2018-07-15
• Subjects: Cavitation modelling -- CFD -- Delft twisted hydrofoil -- PPTC propeller VP1304 -- DES turbulence model -- Mesh refinement; Ocean engineering -- Periodicals; Ocean engineering; Periodicals; 620.4162
• DOI: 10.1016/j.oceaneng.2018.04.064
• Languages: English
• ISSNs: 0029-8018

Abstract

Abstract: This paper presents the ongoing research on cavitation modelling so far which include validation studies to simulate the hydrodynamic characteristics of the Delft twisted hydrofoil and a controllable pitch propeller VP1304 (PPTC propeller) with zero shaft and inclined shaft cavitating flow conditions. Cavitating flow characteristics are modelled by performing Computational Fluid Dynamics (CFD) simulations using Detached Eddy Simulation (DES) method with SST (Menter) k-ω turbulence model. Multiphase viscous flow, water and air, are modelled using Eulerian multiphase approach and motion of the fluid volume throughout the computational domain is modelled with Volume of Fluid (VOF) approach capturing the interface. Cavitation is modelled by Schnerr-Sauer cavitation model with Reboud correction. The predicted three dimensional cavity structures around the twisted hydrofoil agree fairly well with the experimental observations given in open literature. Lift forces predicted using DES calculation are very close to that of the calculated ones, using a recommended quadratic function. The performance of the PPTC propeller for different conditions are conventionally represented in terms of non-dimensional coefficients, i.e., thrust coefficient ( K T ), torque coefficient ( K Q ) and efficiency ( η ) and cavity patterns on the propeller blades compared with the literature show good agreement with the experimental data. Highlights: Applicability of Detached Eddy Simulation (DES) method on hydrodynamic performance and cavitation development of marine propellers is studied. The method accurately predicted cavitation pattern on a hydrofoil as well as on propeller blades. By the way of mesh refinement study, CFD predictions of the propeller characteristics and cavity patterns on and around the propeller are more consistent with the experimental results. Although the DES provided a powerful and reliable tool for understanding the physical mechanisms of the cavitating flow, it is not yet possible to numerically predict all the dynamics of the tip vortex cavitation completely.