Comparison of VLES and LES Turbulence Modeling for Swirling Turbulent Flow

Tiwari, Prashant; Xia, Zhaoyang; Han, Xingsi

doi:10.36884/jafm.13.04.30843

Cited by 8 publications

(5 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Recently, a strong swirling flow, Sr = 1.16 and Sr = 1.23, has also been simulated using the VLES model. The study confirms the validity and accuracy of the VLES model for complex strongly swirling turbulent flow (Xia et al 2020;Tiwari et al 2020).…”

Section: Introductionsupporting

confidence: 77%

Very-Large-Eddy Simulation of Nonreactive Turbulent Flow for Annular Trapped Vortex Combustor

Zhang

Jin

Han

et al. 2022

JAFM

View full text Add to dashboard Cite

A hybrid Reynolds-averaged Navier-Stokes (RANS) large eddy simulation (LES) method is applied in this work. It called very-large-eddy simulation (VLES) turbulence closure model. The aim of this present study is firstly to validate the accuracy of this method for a specific engineering application (a trapped vortex combustor) and secondly to describe its flow characteristics. The trapped vortex combustor is a new concept that utilizes a large recirculation vortex to stabilize the flame. An accurate prediction of the turbulent flow is meaningful for the trapped vortex combustor. The time-averaged velocity, root-mean-square (rms) velocity, and flow pattern are compared with the experimental data. And the LES model, RANS BSL k-ω model, and RANS k-ɛ model are also applied for the simulation with different mesh resolutions. The results show that the VLES BSL k-ω model provides improved accuracy for velocity prediction. The classical large vortex structure for the trapped vortex combustor is captured qualitatively by the VLES BSL k-ω model also. In addition, the vortex breakdown and processing vortex cone are visualized using the Q-criterion. Furthermore, the VLES BSL k-ω model is not sensitive to the gird resolution. The VLES method is able to predict the turbulent flow of trapped vortex combustor relatively well.

show abstract

Section: Introductionsupporting

confidence: 77%

Very-Large-Eddy Simulation of Nonreactive Turbulent Flow for Annular Trapped Vortex Combustor

Zhang

Jin

Han

et al. 2022

JAFM

View full text Add to dashboard Cite

show abstract

“…The improved VLES (IVLES) model was applied to some basic RANS models, such as the standard k − ε model [28] and k − ω model [29], for many tests, and generally good results were obtained for some incompressible or subsonic flows [30][31][32][33]. The VLES method's adaptive resolution control function allowed it to outperform most of the LES models in relatively coarse meshes [27,30,34,35]. Additionally, the resolution control function in the VLES model is independent of the wall distance, making it more suitable for engineering applications with complex configurations and turbulent structures.…”

Section: Introductionmentioning

confidence: 99%

Investigation of Very Large Eddy Simulation Method for Applications of Supersonic Turbulent Combustion

Yan

Cao

et al. 2023

Aerospace

View full text Add to dashboard Cite

The very large eddy simulation (VLES) method was investigated for supersonic reacting flows in the present work. The advantages and characteristics of the VLES model and the widely used improved delayed detached eddy simulation (IDDES) method were revealed through a supersonic ramped-cavity cold flow. Compared to the IDDES model, the VLES model transformed from RANS mode to LES mode faster, resulting in a smaller gray region caused by the mode transition. However, the original volume-averaging truncation length scale could lead to poor predictions of the velocity profiles and wall pressure distribution. By introducing a hybrid truncation length scale combining the maximum grid length and the shear layer adaptive (SLA) length with different coefficients, the accuracy of the VLES method was significantly improved, and the issue of the low shear layer position was solved. Moreover, owing to the resolution control function, the VLES method could adaptively model more turbulent kinetic energy and maintain a good accuracy in a coarser mesh. Finally, the modified VLES method was applied in conjunction with a hybrid combustion model constructed by the partially stirred reactor (PaSR) model and the Ingenito supersonic combustion model (ISCM) in simulations of the supersonic flame in the DLR scramjet combustor. After introducing the correction of the molecular collision frequency by the ISCM, the results obtained by the hybrid combustion model were more consistent with the experimental results, especially for the time-averaging temperature profile in the ignition zone.

show abstract

“…LES methods are very effective for studying various turbulence characteristics of swirl stabilized combustor. They can be effectively used for treatment and studying dissipation of vortex breakdown and swirl structure, as well as angular recirculating zone and central recirculating zone, important characteristics of swirl (Kim et al 2011, Tiwari et al 2020. Canepa et al (2006) has shown that the complex flow field structure comes from vortex breakdown.…”

Section: Introductionmentioning

confidence: 99%

Investigation of Isothermal Flow inside a New Combustor with Two-Stage Axial Swirler

Wang

Wei

Shrotriya

et al. 2022

JAFM

View full text Add to dashboard Cite

Experiments and numerical simulations are performed to study the cold flow field characteristics in a two-stage axial swirl combustion chamber. Large eddy simulation with dynamic turbulent kinetic energy sub-grid scale model is used to calculate the flow field, and particle image velocimetry is used to measure the turbulent flow field. The calculated results are found to be in a good agreement with the experiment results. Due to the shear layers and the density difference between CO2 and air flows, the central recirculation zone appears. With the increase of the ratio of flow velocity between inner and outer tubes, the central recirculation zone shrinks gradually, while the length and range of the angular recirculation zone increase continuously. The vortex structure develops in the axial and radial directions, and the vortex breakdown mostly occurs in the upstream regions. However, outside the central recirculation zone, only one shear layer is observed, and its vortex structure is almost extended up to the exit of the combustion chamber. In addition, precession vortex core is not seen in all the conditions.

show abstract

Comparison of VLES and LES Turbulence Modeling for Swirling Turbulent Flow

Cited by 8 publications

References 18 publications

Very-Large-Eddy Simulation of Nonreactive Turbulent Flow for Annular Trapped Vortex Combustor

Very-Large-Eddy Simulation of Nonreactive Turbulent Flow for Annular Trapped Vortex Combustor

Investigation of Very Large Eddy Simulation Method for Applications of Supersonic Turbulent Combustion

Investigation of Isothermal Flow inside a New Combustor with Two-Stage Axial Swirler

Contact Info

Product

Resources

About