Uncertainty Assessment Using Stochastic Reduced Basis Method for Flow in Porous Media

Placeholder Show Content

Abstract/Contents

Abstract
We apply a hybrid formulation combining the stochastic reduced basis methods with polynomial chaos expansions, which has been introduced recently by Nair [1] for solving the linearized stochastic partial differential equation governing single-phase °ow in porous media. We use a generalization of stochastic reduced basis projection schemes to non- Gaussian uncertainty models. The Karhunen-Loeve expansion is used to model the input log-permeability field; for non-Gaussian input we employ Polynomial Chaos expansion to model the nonlinearity in terms of Hermite polynomials. For the pressure equation, we em- ploy basis vectors spanning the preconditioned stochastic Krylov subspace which efficiently reduces the dimensions of the solution space. Then the Galerkin projection scheme is used to estimate the coefficients of the reduced basis approximations. We present a detailed comparison between high resolution Monte Carlo simulation and the Stochastic Reduced Basis Method (SRBM). We also study the difference between predictions obtained using SRBM with low-order Statistical Moment Equations (SME) and a Probabilistic Collocation Method (PCM). Natural formations with high permeability variability and large spatial correlation scales are of great interest. Consequently, we examine SRBM for systems with a variance of log-permeability from 0.1 to 3 and correlation scales (normalized by domain length) of 0.05 to 0.5. In order to avoid issues related to statistical convergence and resolution level, we used 9000 highly detailed realizations of permeability for Monte Carlo Simulation (MCS). We show that SRBM gives reasonably close results with MCS using a small number of Krylov subspace basis at lower computational cost.

Description

Type of resource text
Date created March 2009

Creators/Contributors

Author Bazargan, Hamid
Primary advisor Tchelepi, Hamdi
Degree granting institution Stanford University, Department of Energy Resources Engineering

Subjects

Subject School of Earth Energy & Environmental Sciences
Genre Thesis

Bibliographic information

Access conditions

Use and reproduction
User agrees that, where applicable, content will not be used to identify or to otherwise infringe the privacy or confidentiality rights of individuals. Content distributed via the Stanford Digital Repository may be subject to additional license and use restrictions applied by the depositor.

Preferred citation

Preferred Citation
Bazargan, Hamid. (2009). Uncertainty Assessment Using Stochastic Reduced Basis Method for Flow in Porous Media. Stanford Digital Repository. Available at: https://purl.stanford.edu/vp177ps3010

Collection

Master's Theses, Doerr School of Sustainability

View other items in this collection in SearchWorks

Contact information

Also listed in

Loading usage metrics...