Projection-based model order reduction and hyperreduction of turbulent flow models

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Abstract/Contents

Abstract
Despite significant advances in simulation-based engineering science in recent decades, time-critical applications struggle to take advantage of high-fidelity, partial differential equation-based computer simulation. This is due to the large processing time and storage requirements associated with large-scale computational models. Projection-based model order reduction (PMOR) methods offer the ability to dramatically reduce this computational cost by generating compact, low-dimensional models for which solutions can be obtained in near real-time while still retaining the accuracy of an associated high-fidelity, high-dimensional model for the time and parameter domain of interest. PMOR is thus an essential technology for the application of model-based control, probabilistic analysis, or design optimization to problems involving increasingly complex engineered systems and physical phenomena. Unfortunately, nonlinear problems, in particular turbulent computational fluid dynamics (CFD) applications, continue to present a number of challenges for constructing stable, accurate, and computationally efficient projection-based reduced order models (PROMs). This thesis addresses some of these challenges, demonstrating PROMs for a number of large-scale, unsteady, turbulent flow applications which showcase the potential of PMOR for nonlinear CFD models with multiscale physics. These results leverage advancements in hyperreduction, a technique for the treatment of nonlinearities in the underlying computational model, to obtain CPU time and wall-clock time speedup factors of several orders of magnitude. This work also presents an investigation of the role of projection in the numerical stability of PMOR for convection-dominated flow problems, ultimately disproving an often-stated claim in the literature with the support of several numerical examples

Description

Type of resource text
Form electronic resource; remote; computer; online resource
Extent 1 online resource
Place California
Place [Stanford, California]
Publisher [Stanford University]
Copyright date 2020; ©2020
Publication date 2020; 2020
Issuance monographic
Language English

Creators/Contributors

Author Grimberg, Sebastian Johannes
Degree supervisor Farhat, Charbel
Thesis advisor Farhat, Charbel
Thesis advisor Alonso, Juan José, 1968-
Thesis advisor Lele, Sanjiva K. (Sanjiva Keshava), 1958-
Degree committee member Alonso, Juan José, 1968-
Degree committee member Lele, Sanjiva K. (Sanjiva Keshava), 1958-
Associated with Stanford University, Department of Aeronautics & Astronautics

Subjects

Genre Theses
Genre Text

Bibliographic information

Statement of responsibility Sebastian J. Grimberg
Note Submitted to the Department of Aeronautics & Astronautics
Thesis Thesis Ph.D. Stanford University 2020
Location electronic resource

Access conditions

Copyright
© 2020 by Sebastian Johannes Grimberg
License
This work is licensed under a Creative Commons Attribution Non Commercial 3.0 Unported license (CC BY-NC).

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