A new simpler rotation/curvature correction method for Spalart–Allmaras turbulence model

Purpose – The purpose of this paper is to assess the predictive capability of the streamline curvature correction model (CCM) and investigate the unsteady vortex behavior of the cloud cavitating flows around a hydrofoil. Design/methodology/approach – The design of the paper is based on introducing the curvature correction method to the original k-ε model. Calculations of unsteady cloud cavitating flows around a Clark-Y hydrofoil are performed using both the CCM and the baseline model. Findings – Compared with the baseline model, better agreements are observed between the predictions of the CCM model and experimental data, especially the cavity shedding process. Based on the computations, it is demonstrated that streamline curvature correction of the CCM model can effectively decrease predicted turbulence kinetic energy and eddy viscosity in cavity shedding region. This leads to the better prediction for the recirculation zone located downstream of the attached cavity, and dynamics of this recirculation zone contribute to the formation and development of the re-entrant jet. Originality/value – The authors apply streamline curvature correction to the calculations of unsteady cloud cavitating flows and discuss the interactions between the cavitation unsteadiness and vortex structures to get an insight of the correction mechanics.

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Evaluation of the Turbulence Model Influence on the Numerical Simulation of Cavitating Flow with Emphasis on Temperature Effect

Processes ◽

10.3390/pr8080997 ◽

2020 ◽

Vol 8 (8) ◽

pp. 997

Author(s):

Yilin Deng ◽

Jian Feng ◽

Fulai Wan ◽

Xi Shen ◽

Bin Xu

Keyword(s):

Numerical Simulation ◽

Temperature Effect ◽

Turbulence Model ◽

Numerical Solutions ◽

Turbulent Viscosity ◽

Turbulence Models ◽

Correction Method ◽

Cavitating Flow ◽

Density Correction ◽

Different Temperatures

The aim of this paper is to investigate the influence of different turbulence models (k−ε, RNG k−ε, and SST k−ω) on the numerical simulation of cavitating flow in thermosensitive fluid. The filter-based model and density correction method were employed to correct the turbulent viscosity of the three turbulence models. Numerical results obtained were compared to experimental ones which were conducted on the NACA0015 hydrofoil at different temperatures. The applicability of the numerical solutions of different turbulence model was studied in detail. The modified RNG k−ε model has higher accuracy in the calculation of cavitating flow at different temperatures.

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Assessment of the modified rotation/curvature correction SST turbulence model for simulating swirling reacting unsteady flows in a solid-fuel ramjet engine

Acta Astronautica ◽

10.1016/j.actaastro.2016.09.016 ◽

2016 ◽

Vol 129 ◽

pp. 241-252 ◽

Cited By ~ 12

Author(s):

Omer Musa ◽

Chen Xiong ◽

Zhou Changsheng ◽

Gong Lunkun

Keyword(s):

Turbulence Model ◽

Solid Fuel ◽

Unsteady Flows ◽

Curvature Correction ◽

Ramjet Engine ◽

Sst Turbulence Model

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Numerical analysis of the unsteady cavitation shedding flow around twisted hydrofoil based on hybrid filter model

Thermal Science ◽

10.2298/tsci1804629z ◽

2018 ◽

Vol 22 (4) ◽

pp. 1629-1636

Author(s):

Desheng Zhang ◽

Jian Chen ◽

Lei Shi ◽

Guangjian Zhang ◽

Weidong Shi ◽

...

Keyword(s):

Turbulence Model ◽

High Speed ◽

Adverse Pressure Gradient ◽

Correction Method ◽

High Speed Photography ◽

Filter Model ◽

University Of Technology ◽

Development Cycle ◽

Filter Size ◽

Cavity Evolution

Cavitation is a common phenomenon in components of fluid machinery and it may induce material damage and vibration. A more accurate and commercial turbulence model is required to predict cavitation. In this paper, we make a combination of filter-based model (FBM) and density correction method (DCM) to propose a new DCM FBM. Firstly, the new DCM FBM and the homogeneous cavitation model are validated by comparing the simulation result with the experiment of cavitation shedding flow around the Clark-y hydrofoil and the filter size is determined as well. Then, the cavitation pattern cycle and shedding vortex structure of the twist hydrofoil experimented by Delft University of Technology were predicted using the DCM FBM. The predicted 3-D cavitation structures and development cycle of twist hydrofoil as well as the collapsing features show a good qualitative agreement with the high speed photography results. Numerical results show that the improved turbulence model could predict the cloud cavity evolution well, including the cloud cavity generation, shedding and dissipation. It is found that the re-entrant jet induced by the by adverse pressure gradient is the main reason to generate the cloud cavity shedding. The secondary shedding is al-so observed which is result from the combination of the radially advancing re-entrant jet and side-entrant jet simulated by the DCM FBM turbulence method.

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