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Reynolds stress model involving the mean spin tensor
1State Key Laboratory for Turbulence and Complex Systems, Department of Mechanics and Engineering Science, Peking University, Beijing 100871, People's Republic of China.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|November 5, 2004
Summary
This study introduces a new Reynolds stress model incorporating the mean spin tensor for improved turbulence modeling. The model shows good agreement with experimental data and DNS, outperforming previous quadratic models.
Area of Science:
- Fluid Dynamics
- Turbulence Modeling
Background:
- Reynolds stress models are crucial for simulating turbulent flows.
- Existing models often neglect the influence of the mean spin tensor.
Purpose of the Study:
- To develop and assess a novel Reynolds stress model that includes the mean spin tensor.
- To evaluate the contribution of the mean spin tensor in turbulence modeling.
Main Methods:
- Developed a constitutive functional for Reynolds stress dependent on mean spin and stretching tensors, turbulent kinetic energy (K), and dissipation rate (epsilon).
- Utilized representation theorem and theory of invariants from rational continuum mechanics.
- Derived a nonlinear cubic K-epsilon model with analytically identified coefficients using experimental data.
Main Results:
- The new model, using both Jaumann and Oldroyd derivatives, demonstrated good agreement with experimental and DNS data for homogeneous turbulent shear flow and backward-facing step flow.
- The model outperformed previously developed quadratic models.
Conclusions:
- The mean spin tensor plays a significant role in turbulence modeling.
- The proposed Reynolds stress model offers improved accuracy and performance compared to existing models.
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