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arXiv · 1711.11275

Stabilized weighted reduced basis methods for parametrized advection dominated problems with random inputs

Davide Torlo·Francesco Ballarin·Gianluigi Rozza
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Abstract

In this work, we propose viable and efficient strategies for stabilized parametrized advection dominated problems, with random inputs. In particular, we investigate the combination of wRB (weighted reduced basis) method for stochastic parametrized problems with stabilized reduced basis method, which is the integration of classical stabilization methods (SUPG, in our case) in the Offline--Online structure of the RB method. Moreover, we introduce a reduction method that selectively enables online stabilization; this leads to a sensible reduction of computational costs, while keeping a very good accuracy with respect to high fidelity solutions. We present numerical test cases to assess the performance of the proposed methods in steady and unsteady problems related to heat transfer phenomena.

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Davide Torlo, Francesco Ballarin, Gianluigi Rozza. 2017-11-30. Stabilized weighted reduced basis methods for parametrized advection dominated problems with random inputs. https://doi.org/10.1137/17m1163517

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