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Title: An efficient algorithm for simulating ensembles of parameterized flow problems
Abstract Many applications of computational fluid dynamics require multiple simulations of a flow under different input conditions. In this paper, a numerical algorithm is developed to efficiently determine a set of such simulations in which the individually independent members of the set are subject to different viscosity coefficients, initial conditions and/or body forces. The proposed scheme, when applied to the flow ensemble, needs to solve a single linear system with multiple right-hand sides, and thus is computationally more efficient than solving for all the simulations separately. We show that the scheme is nonlinearly and long-term stable under certain conditions on the time-step size and a parameter deviation ratio. A rigorous numerical error estimate shows the scheme is of first-order accuracy in time and optimally accurate in space. Several numerical experiments are presented to illustrate the theoretical results.  more » « less
Award ID(s):
1720001 2120413
PAR ID:
10161586
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
IMA Journal of Numerical Analysis
Volume:
39
Issue:
3
ISSN:
0272-4979
Page Range / eLocation ID:
1180 to 1205
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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