Numerical simulation of the three-dimensional unsteady cavitating flow around a twisted hydrofoil

2019 ◽  
Vol 188 ◽  
pp. 106313 ◽  
Author(s):  
Zhihui Liu ◽  
Benlong Wang
Keyword(s):  
Numerical Simulation ◽  
Three Dimensional ◽  
Cavitating Flow ◽  
Twisted Hydrofoil ◽  
Unsteady Cavitating Flow

Lagrangian Analysis of Unsteady Partial Cavitating Flow Around a Three-Dimensional Hydrofoil

2020 ◽  
Author(s):  
Tingyun Yin ◽  
Giorgio Pavesi ◽  
Ji Pei ◽  
Shouqi Yuan ◽  
Giovanna Cavazzini ◽  
...  
Keyword(s):  
Coherent Structure ◽  
Cavity Growth ◽  
Three Dimensional ◽  
Adverse Pressure Gradient ◽  
Buffer Zone ◽  
Cavitating Flow ◽  
Lagrangian Analysis ◽  
Lagrangian Coherent Structure ◽  
Cavity Development ◽  
Unsteady Cavitating Flow

Abstract This study employs an incompressible homogeneous flow framework with a transport-equation-based cavitation model and shear stress transport turbulence model to successfully reproduce the unsteady cavitating flow around a three-dimensional hydrofoil. Cavity growth, development, and break-off during the periodic shedding process are adequately reproduced and match experimental observations. The predicted shedding frequency is very close to the experimental value of 23 ms. By monitoring the motions of the seeding trackers, growth-up of attached cavity and dynamic evolution of U-type cavity are clearly displayed, which indicating the trackers could serve as an effective tool to visualize the cavitating field. Repelling Lagrangian Coherent Structure (RLCS) is so complex that abundant flow patterns are highlighted, reflecting the intricacy of cavity development. The formation of cloud cavities is clearly characterized by the Attracting Lagrangian Coherent Structure (ALCS), where bumbling wave wrapping the whole shedding cavities indicates the rotating transform of cavities and stretching of the wave eyes shows the distortion of vortices. Generation of the re-entrant jet is considered to be not only associated with the adverse pressure gradient due to the positive attack angle, but also the contribution of cloud cavitating flow, based on the observation of a buffer zone between the attached and cloud cavities.

G704 Numerical Simulation of the Unsteady Cavitating Flow in an Inducer for Turbopump(1)

2006 ◽  
Vol 2006 (0) ◽  
pp. _G704-a_
Author(s):  
Hiroki Ugajin ◽  
Masafumi Kawai ◽  
Kohei Okita ◽  
Yoichiro Matsumoto ◽  
Takeo Kajishima ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Cavitating Flow ◽  
Unsteady Cavitating Flow

scholarly journals Effects of Wavy Leading-Edge Protuberance on Hydrofoil Performance and Its Flow Mechanism

2021 ◽  
Vol 9 (10) ◽  
pp. 1138
Author(s):  
Jing Li ◽  
Chunbao Liu ◽  
Xiaoying Li
Keyword(s):  
Flow Instability ◽  
Three Dimensional ◽  
Leading Edge ◽  
Streamwise Vortex ◽  
Cavitating Flow ◽  
Cavitation Inception ◽  
Vortex Interactions ◽  
Cavitation Pressure ◽  
Les Model ◽  
Unsteady Cavitating Flow

This paper examines the effects on a Clark-y three-dimensional hydrofoil of wavy leading-edge protuberances in a quantitative and qualitative way. The simulation is accompanied by a hybrid RANS-LES model in conjunction with Zwart-Gerber–Belamri model. Detailed discussions of the stable no-cavitating, unsteady cavitating flow fields and the control mechanics are involved. The force characteristics, complicated flow behaviors, cavitation–streamwise vortex interactions, and the cavitating flow instability are all presented. The results demonstrate that protuberances acting as vortex generators produce a continuous influx of boundary-layer vorticity, significantly enhancing the momentum transfer of streamwise vortices and therefore improving the hydrodynamics of the hydrofoil. Significant interactions are described, including the encouragement impact of cavitation evolution on the fragmentation of streamwise vorticities as well as the compartmentation effect of streamwise vorticities binding the cavitation inception inside the troughs. The variations in cavitation pressure are mainly due to the acceleration in steam volume. In summary, it is vital for new hydrofoils or propeller designs to understand in depth the effects of leading-edge protuberances on flow control.

Large Eddy Simulation of Unsteady Cavitating Flow Around a Highly Skewed Propeller in Nonuniform Wake

2017 ◽  
Vol 139 (4) ◽  
Author(s):  
Chao Yu ◽  
Yiwei Wang ◽  
Chenguang Huang ◽  
Xiaocui Wu ◽  
Tezhuan Du
Keyword(s):  
Numerical Simulation ◽  
High Speed ◽  
Large Scale ◽  
Cavitating Flow ◽  
Ship Wake ◽  
Factors Affecting ◽  
Eddy Simulation ◽  
Subgrid Model ◽  
Large Eddy ◽  
Unsteady Cavitating Flow

Unsteady cavitating flows around propellers become increasingly prominent on large-scale and high-speed ships, but large eddy simulations (LES) are limited in the literature. In this study, numerical simulation of an unsteady cavitating flow around a highly skewed propeller in a nonuniform wake is performed based on an explicit LES approach with k−μ subgrid model. Kunz cavitation model, volume of fluid (VOF) method, and a moving mesh scheme are adopted. The predicted evolution of the unsteady cavitating flow around a highly skewed propeller in a nonuniform ship wake is in good agreement with experimental results. An analysis of the factors affecting the cavitation on the propeller is conducted based on numerical simulation. Furthermore, the influences between cavitation structures and vortex structures are also briefly analyzed.

Sign in / Sign up

Export Citation Format

Share Document