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Assistant Professor, Imam Hossein University, Tehran, Iran
Abstract
Most fluid systems involve turbulent flows, which require the use of turbulence models for numerical simulation. These models are generally classified into two main groups, namely Reynolds-Averaged Navier-Stokes (RANS) models and Large Eddy Simulation (LES) models. Despite their high accuracy, existing turbulence models typically involve significant computational costs. In this study, a novel and accurate method with low computational complexity is proposed for modeling subgrid scales based on fractal theory within the LES framework. This model belongs to the category of non-eddy-viscosity models and operates through the artificial reconstruction of the velocity field. It has been implemented within the open-source OpenFOAM package. The proposed model utilizes simple assumptions to derive subgrid effects from the behavior of larger-scale grid eddies. Fractal interpolation is employed to improve accuracy and reduce computational costs. The main innovation of the present study is the development of a new and simplified subgrid-scale model utilizing fractal interpolation, making it more efficient for use within the LES approach. To validate the model’s capabilities, turbulent flow in a three-dimensional periodic channel at various Reynolds numbers has been simulated. Turbulent flow parameters have been accurately predicted and compared with strong subgrid-scale (SGS) models such as the Dynamic Smagorinsky Model (DSM) and the Deardorff Stress Model, as well as with a model-free laminar flow solution. The results indicate that the proposed model can significantly reduce computational costs while maintaining the required accuracy.
Bagheri, A., & Vaziri, M. A. (2025). Development of a Low-Cost Subgrid Model Based on Fractal Theory for Turbulent Flow. Fluid Mechanics & Aerodynamics, 14(1), -.
MLA
Amir Bagheri; Mohammad Ali Vaziri. "Development of a Low-Cost Subgrid Model Based on Fractal Theory for Turbulent Flow", Fluid Mechanics & Aerodynamics, 14, 1, 2025, -.
HARVARD
Bagheri, A., Vaziri, M. A. (2025). 'Development of a Low-Cost Subgrid Model Based on Fractal Theory for Turbulent Flow', Fluid Mechanics & Aerodynamics, 14(1), pp. -.
VANCOUVER
Bagheri, A., Vaziri, M. A. Development of a Low-Cost Subgrid Model Based on Fractal Theory for Turbulent Flow. Fluid Mechanics & Aerodynamics, 2025; 14(1): -.
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