Article
Thermodynamics
L. J. Zhai, H. X. Chen, Z. Ma
Summary: A new turbulent model based on DDES and NLEVM was developed to predict complex turbulent flow. Numerical simulations of a triangular cylinder and a centrifugal pump demonstrated the accuracy and applicability of the model in predicting flow phenomena and flow structures.
JOURNAL OF APPLIED FLUID MECHANICS
(2022)
Article
Engineering, Marine
Linfeng Deng, Yun Long, Bin Ji
Summary: Delayed detached eddy simulation (DDES) together with a homogeneous cavitation model is used to investigate the cavitating flow around a marine propeller behind the hull. The study pays particular attention to the effect of cavitation on simulation errors distribution and vortex dynamics. The results show good agreement between the predicted cavitation pattern and pressure fluctuation and the experimental results. Additionally, the study assesses simulation accuracy by calculating DDES errors and examines the cavitation-vortex interaction using the vorticity transport equation.
Article
Energy & Fuels
Wubingyi Shen, Yue Huang, Wei Yao, Hedong Liu, Yancheng You
Summary: The purpose of this study is to investigate the influence of diffusion characteristics and equivalence ratios of gaseous/liquid kerosene on transient combustions in a three-dimensional combustor. The similarities and differences between gaseous and liquid kerosene supersonic combustion are identified. Results show significant differences in injection velocity and residence time between gaseous and liquid kerosene, as well as differences in reaction heat release position.
Article
Computer Science, Interdisciplinary Applications
Jagdeep Batther, Seongkyu Lee
Summary: This study examines the flow physics and predictability of Delayed Detached Eddy Simulations (DDES) in relation to the dynamic stall onset process. The comparison with Large Eddy Simulations (LES) shows that DDES is able to capture important phenomena and predict an earlier lift stall onset.
COMPUTERS & FLUIDS
(2022)
Article
Environmental Sciences
Zhenye Sun, Rongkun Shi, Weijun Zhu, Xiaochuan Li, Junwei Yang
Summary: The continuous increase in wind turbine blade length raises the question of reducing blade mass effectively. This paper focuses on airfoils with thickness to chord ratios of 30% and investigates the influence of spanwise length on the numerical results. It is found that the spanwise length has a crucial influence on lift and drag prediction.
Article
Mechanics
Lipeng Qu, Shujaut H. Bader, Zifei Yin
Summary: Driven by the need for simulating compressible flows, dynamic models based on Germano identity and Vreman operator are constructed to handle compressible boundary layers and shock-boundary layer interaction. The new dynamic model based on k-ω SST overcomes issues of freestream sensitivity and inaccurate compressible boundary layer profile. The Vreman-dynamic model using the Vreman operator predicts a reattachment location similar to the zonal improved-DDES/direct numerical simulation approach.
Article
Mathematics
Evgeny V. Solomin, Gleb N. Ryavkin
Summary: The known differential yaw error of horizontal axis wind turbines is caused by weather vane fluctuations due to the deflection of the wind flow from the rotating blades. This paper focuses on the computational fluid dynamics and experimental study of the aerodynamic characteristics of the weather vane on horizontal axis wind turbines. The results obtained during the study expand upon the experience of using numerical simulation and may be used to build mathematical models of yaw control systems.
Article
Engineering, Multidisciplinary
Yun Long, Chengzao Han, Xinping Long, Bin Ji, Hongbo Huang
Summary: The Delayed Detached Eddy Simulation (DDES) technique was used to analyze unsteady cavitating turbulent flow around a hydrofoil and a highly skewed marine propeller behind a ship hull. The numerical results were in good agreement with experimental data, showing the accuracy of the DDES method. It was found that shedding vortices and large-scale vortex were the main sources of DDES errors, with mesh resolution playing a key role in reproducing finer flow structures.
APPLIED MATHEMATICAL MODELLING
(2021)
Article
Engineering, Aerospace
Minjae Jeong, Yeji Yun, Seoyeon Heo, Solkeun Jee
Summary: In this study, axisymmetric base flow is used to investigate the flow physics of massive flow separation at a subsonic speed. The detached-eddy simulation (DES) approach is employed to accurately capture the separated flow from the base. By systematically designing the computational grid, the spatial resolution in the large-eddy simulation (LES) zone is improved for better fidelity of the DES computation. The axisymmetric base flow is well resolved in the current DES simulation, showing good agreement with experimental data and allowing for further statistical analysis of the separated flow.
INTERNATIONAL JOURNAL OF AERONAUTICAL AND SPACE SCIENCES
(2023)
Article
Mechanics
Nabil M. Khalifa, Amirsaman Rezaei, Haithem E. Taha
Summary: In this paper, the three-dimensional nature of dynamic stall is investigated through numerical simulations and experimental measurements. The results show that three-dimensional simulations capture the stages of dynamic stall and predict the lift coefficient values more accurately than two-dimensional simulations, with the DES solvers performing better than the URANS ones. Therefore, it is concluded that dynamic stall is intrinsically a three-dimensional phenomenon.
Article
Physics, Applied
Bo Luo, Wuli Chu, Song Yan, Zhengjing Shen, Haoguang Zhang
Summary: This study compared the accuracy and computational requirements of IDDES and LES in predicting unsteady flows and noise generated by a circular cylinder, finding that IDDES retains much of the numerical accuracy of LES while requiring reduced computational resources.
MODERN PHYSICS LETTERS B
(2021)
Article
Mechanics
Quanzheng Li, Xin Chen, Gang Wang, Yi Liu
Summary: This paper develops a dynamic version of RSM-DynIDDES, which simulates the periodic hills flow and the transonic buffeting of a launch vehicle with a payload fairing. By applying the dynamic Smagorinsky subgrid model to the LES branch of IDDES, RSM-DynIDDES captures small-scale vortex structures and improves turbulence resolution in the off-wall region.
Article
Engineering, Mechanical
Zifei Yin, Paul A. Durbin
Summary: This study selected the adaptive L(2)-omega delayed detached eddy simulation model and tested various turbulent intensities to evaluate its performance in simulating transitional separated flow in a linear compressor cascade. The results showed that the adaptive model had the capability to accurately capture the laminar boundary layer and large-scale disturbances, and predict the transition front to the turbulent boundary layer. It also accurately predicted the size of the separation bubble in separation-induced transition.
JOURNAL OF TURBOMACHINERY-TRANSACTIONS OF THE ASME
(2022)
Article
Engineering, Civil
Tong Zhou, Qingshan Yang, Bowen Yan, Xiaowei Deng, Yangjin Yuan
Summary: This study evaluates the performance of different turbulence models in simulating turbulent flow fields, finding that the DDES model based on SST k-w can better predict velocity and turbulence fluctuation profiles, while the DES and DDES models based on S-A excel in reproducing spectral characteristics.
JOURNAL OF WIND ENGINEERING AND INDUSTRIAL AERODYNAMICS
(2022)
Article
Energy & Fuels
Zhonghua Sheng, Guogang Yang, Wei Gao, Shian Li, Qiuwan Shen, Han Sun
Summary: This study investigates the dynamic behavior of premixed hydrogen-air deflagration flame propagation in a closed tube using the Large Eddy Simulation technique. By comparing four different types of turbulent flame wrinkling models, the dynamic wrinkling model is found to have a high level of accuracy in predicting flame behavior. The numerical results show five forms of flame evolution and the influence of obstacle arrangements on flame propagation speed and deflagration overpressure. The flame propagation process is mainly influenced by the coupling of Rayleigh-Taylor and Kelvin-Helmholtz instability mechanisms.
Article
Thermodynamics
Zifei Yin, Paul A. Durbin
FLOW TURBULENCE AND COMBUSTION
(2017)
Article
Thermodynamics
Zifei Yin, Paul A. Durbin
INTERNATIONAL JOURNAL OF HEAT AND FLUID FLOW
(2016)
Article
Engineering, Mechanical
Paul Durbin, Zifei Yin, Elbert Jeyapaul
JOURNAL OF FLUIDS ENGINEERING-TRANSACTIONS OF THE ASME
(2016)
Article
Thermodynamics
K. R. Reddy, J. A. Ryon, P. A. Durbin
INTERNATIONAL JOURNAL OF HEAT AND FLUID FLOW
(2014)
Article
Mechanics
Zifei Yin, Xuan Ge, Paul Durbin
Summary: The study explores the transitional behavior of turbulence and the use of the l(2)-omega adaptive detached eddy simulation model. The model dynamically adjusts model constants between laminar and turbulent flows, effectively capturing the transitional behavior of turbulence. The research also evaluates the predictive mechanism of the adaptive model and its sensitivity to boundary conditions and mesh resolution.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Engineering, Mechanical
Zifei Yin, Paul A. Durbin
Summary: This study selected the adaptive L(2)-omega delayed detached eddy simulation model and tested various turbulent intensities to evaluate its performance in simulating transitional separated flow in a linear compressor cascade. The results showed that the adaptive model had the capability to accurately capture the laminar boundary layer and large-scale disturbances, and predict the transition front to the turbulent boundary layer. It also accurately predicted the size of the separation bubble in separation-induced transition.
JOURNAL OF TURBOMACHINERY-TRANSACTIONS OF THE ASME
(2022)
Article
Thermodynamics
Shujaut H. Bader, Zifei Yin, Paul A. Durbin
Summary: This paper presents a simple method for locally computing the model coefficient CDEs based on Vreman's structural function B-beta, without involving explicit filtering or averaging procedures. The model is expected to retain relatively small dissipation in transitional and near-wall regions, making it suitable for predicting transitional flows. Validation of the formulation is done in various flow scenarios.
FLOW TURBULENCE AND COMBUSTION
(2022)
Article
Computer Science, Interdisciplinary Applications
Shujaut H. Bader, Zifei Yin, Paul A. Durbin
Summary: This paper reproduces an experiment conducted by Blair (1983) on flat plate transition under freestream turbulence with heat transfer using subgrid dynamic scalar-flux models. An improved Higher Order Generalized Gradient Diffusion Hypothesis (HOGGDH) model is proposed with a modified, spatially varying model coefficient based on observations to increase accuracy near the wall. The improved version of the HOGGDH model shows accurate predictions of mean temperature and scalar flux compared to other models.
COMPUTERS & FLUIDS
(2022)
Article
Thermodynamics
Haochen Liu, Zifei Yin, Wenwen Xie, Bin Zhang, Jialing Le, Hong Liu
Summary: This study assesses different combustion models for large eddy simulation using direct numerical simulation (DNS). The results show that the PaSR model performs best in most cases, while the EDC model is similar to the QL model at low turbulent Reynolds number. Both the EDC and PaSR models are suitable for high turbulent Reynolds number and medium Karlovitz number conditions. Theoretical analysis helps explain the observations and predict the models' behaviors.
FLOW TURBULENCE AND COMBUSTION
(2022)
Article
Physics, Multidisciplinary
Han Han, Zifei Yin, Yijun Ning, Hong Liu
Summary: This study develops a 3D icing simulation code using the open-source CFD toolbox OpenFOAM, which utilizes a hybrid meshing method and solves the Reynolds-averaged Navier-Stokes equations to simulate the flow field around an airfoil. Different droplet tracking methods are implemented to simulate droplet behavior. Through validation and application examples, it is demonstrated that the simulation code is feasible and accurate in predicting ice shapes.
