Uncertainity propogation in multiphysics systems

Placeholder Show Content

Abstract/Contents

Abstract
Multiphysics systems governed by coupled partial differential equations (PDEs) are naturally suited for modular (partitioned) numerical solution strategies. Although widely used in deterministic simulations, several challenges arise in extending the benefits of modularization to stochastic simulation i.e. uncertainty propagation. Monolithic (black-box) Monte Carlo (MC) based sampling methods ignore the potentially exploitable structures within the multiphysics model, and are generally unreliable because the cost of each PDE solve is significantly high. On the other hand, spectral methods, for instance, generalized polynomial chaos (gPC) based methods, would succumb to the curse of dimensionality, if implemented in their standard (traditional) form, as the coupled nature of the model dictates that each module should handle the combined parameter space for uncertainty propagation. In this thesis, we present a practical module-based framework and efficient spectral methods for uncertainty propagation in multiphysics systems with uncertain parameters. Our proposed framework facilitates complete module-based modeling independence, wherein each module only handles its local uncertain parameters, employing the best suited method. Moreover, the proposed reduced non-intrusive (NISP) and reduced intrusive spectral projection (ISP) methods mitigate the curse of dimensionality by constructing reduced dimensional (and order) approximations of the data communicated between modules and iterations. We demonstrate implementations of our proposed methods on several benchmark test problems, and illustrate their superior performance over standard monolithic methods.

Description

Type of resource text
Form electronic; electronic resource; remote
Extent 1 online resource.
Publication date 2015
Issuance monographic
Language English

Creators/Contributors

Associated with Mittal, Akshay
Associated with Stanford University, Institute for Computational and Mathematical Engineering.
Primary advisor Iaccarino, Gianluca
Thesis advisor Iaccarino, Gianluca
Thesis advisor Kitanidis, P. K. (Peter K.)
Thesis advisor Tong, Charles
Advisor Kitanidis, P. K. (Peter K.)
Advisor Tong, Charles

Subjects

Genre Theses

Bibliographic information

Statement of responsibility Akshay Mittal.
Note Submitted to the Institute for Computational and Mathematical Engineering.
Thesis Thesis (Ph.D.)--Stanford University, 2015.
Location electronic resource

Access conditions

Copyright
© 2015 by Akshay Mittal

Also listed in

Loading usage metrics...