Sensitivity analysis on chaotic dynamical system by Non-Intrusive Least Square Shadowing (NILSS)

Angxiu Ni; Qiqi Wang

doi:10.1016/j.jcp.2017.06.033

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arXiv · 1611.00880

Sensitivity analysis on chaotic dynamical system by Non-Intrusive Least Square Shadowing (NILSS)

Angxiu Ni·Qiqi Wang

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Abstract

This paper develops the non-intrusive formulation of the Least-squares shadowing (LSS) method, for computing the sensitivity of long-time averaged objectives in chaotic dynamical systems. This non-intrusive formulation constrains the computation to only the unstable subspace, greatly reducing the cost of LSS for many problems; moreover, it reparametrizes the LSS problem, requiring only minor modifications to existing tangent solvers. NILSS is demonstrated on a chaotic flow over a backward-facing step simulated with a mesh of 12e3 cells.

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physics.comp-ph cs.CE cs.NA math.NA nlin.CD

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Angxiu Ni, Qiqi Wang. 2016-11-03. Sensitivity analysis on chaotic dynamical system by Non-Intrusive Least Square Shadowing (NILSS). https://doi.org/10.1016/j.jcp.2017.06.033

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