Analysis of Model Variance for Ensemble Based Turbulence Modeling

Date

2015-04-01

Author

Jiang, Nan
Kaya Merdan, Songül
Layton, William

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This report develops an ensemble or statistical eddy viscosity model. The model is parameterized by an ensemble of solutions of an ensemble-Leray regularization. The combined approach of ensemble time stepping and ensemble eddy viscosity modeling allows direct parametrization of the turbulent viscosity co-efficient. We prove unconditional stability and that the model's solution approaches statistical equilibrium as t -> infinity; the model's variance converges to zero as t -> infinity. The ensemble method is used to interrogate a rotating flow, testing its predictability by computing effiective averaged Lyapunov exponents.

Subject Keywords

Applied Mathematics, Numerical Analysis, Computational Mathematics

URI

https://hdl.handle.net/11511/45878

Journal

COMPUTATIONAL METHODS IN APPLIED MATHEMATICS

DOI

https://doi.org/10.1515/cmam-2014-0029

Collections

Department of Mathematics, Article

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Citation Formats

N. Jiang, S. Kaya Merdan, and W. Layton, “Analysis of Model Variance for Ensemble Based Turbulence Modeling,” COMPUTATIONAL METHODS IN APPLIED MATHEMATICS, pp. 173–188, 2015, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/45878.