کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
655597 1457639 2013 11 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
A dynamic global-coefficient mixed subgrid-scale model for large-eddy simulation of turbulent flows
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی جریان سیال و فرایندهای انتقال
پیش نمایش صفحه اول مقاله
A dynamic global-coefficient mixed subgrid-scale model for large-eddy simulation of turbulent flows
چکیده انگلیسی

A dynamic global-coefficient mixed subgrid-scale eddy-viscosity model for large-eddy simulation of turbulent flows in complex geometries is developed. In the present model, the subgrid-scale stress is decomposed into the modified Leonard stress, cross stress, and subgrid-scale Reynolds stress. The modified Leonard stress is explicitly computed assuming a scale similarity, while the cross stress and the subgrid-scale Reynolds stress are modeled using the global-coefficient eddy-viscosity model. The model coefficient is determined by a dynamic procedure based on the global-equilibrium between the subgrid-scale dissipation and the viscous dissipation. The new model relieves some of the difficulties associated with an eddy-viscosity closure, such as the nonalignment of the principal axes of the subgrid-scale stress tensor and the strain rate tensor and the anisotropy of turbulent flow fields, while, like other dynamic global-coefficient models, it does not require averaging or clipping of the model coefficient for numerical stabilization. The combination of the global-coefficient eddy-viscosity model and a scale-similarity model is demonstrated to produce improved predictions in a number of turbulent flow simulations.


► A new SGS model is developed for LES of turbulent flows in complex geometries.
► A dynamic global-coefficient SGS model is coupled with a scale-similarity model.
► Overcome some of difficulties associated with eddy-viscosity closures.
► Does not require averaging or clipping of the model coefficient for stabilization.
► The predictive capability is demonstrated in a number of turbulent flow simulations.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: International Journal of Heat and Fluid Flow - Volume 42, August 2013, Pages 94–104
نویسندگان
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