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arXiv · 2508.11309

Combining Nonlinear FETI-DP Methods and Quasi-Newton Methods using an SQP Approach

Stephan Köhler·Oliver Rheinbach
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Abstract

The combination of nonlinear FETI-DP (Dual Primal Finite Element Tearing and Interconnecting) and Quasi-Newton methods using a sequential quadratic programming (SQP) approach is considered. Nonlinear FETI-DP methods are parallel iterative solution methods for nonlinear finite element problems, based on divide and conquer, using Lagrange multipliers. In the method, we use Quasi-Newton approximations of Hessian for the quadratic programs, where the initial approximation uses the exact Hessian. To accelerate the convergence, we recompute the initial Hessian and restart the Quasi-Newton approximation. We provide numerical experiments using homogeneous model problems from nonlinear structural mechanics.

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Stephan Köhler, Oliver Rheinbach. 2025-08-15. Combining Nonlinear FETI-DP Methods and Quasi-Newton Methods using an SQP Approach. https://arxiv.org/abs/2508.11309

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