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Title: Variational data assimilation with finite-element discretization for second-order parabolic interface equation
Abstract In this paper, we propose and analyze a finite-element method of variational data assimilation for a second-order parabolic interface equation on a two-dimensional bounded domain. The Tikhonov regularization plays a key role in translating the data assimilation problem into an optimization problem. Then the existence, uniqueness and stability are analyzed for the solution of the optimization problem. We utilize the finite-element method for spatial discretization and backward Euler method for the temporal discretization. Then based on the Lagrange multiplier idea, we derive the optimality systems for both the continuous and the discrete data assimilation problems for the second-order parabolic interface equation. The convergence and the optimal error estimate are proved with the recovery of Galerkin orthogonality. Moreover, three iterative methods, which decouple the optimality system and significantly save computational cost, are developed to solve the discrete time evolution optimality system. Finally, numerical results are provided to validate the proposed method.  more » « less
Award ID(s):
2152609
PAR ID:
10583441
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Oxford Academic
Date Published:
Journal Name:
IMA Journal of Numerical Analysis
Volume:
45
Issue:
1
ISSN:
0272-4979
Page Range / eLocation ID:
451 to 493
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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