Application of lRBF-FD Method for Numerical Solution of the Obstacle Problem
- Department of Mathematics, Isf. C., Islamic Azad University, Isfahan
- Department of Mathematics, College of Computer and Mathematics, Uinversity of Thi-Qar, Iraq
Received: 03-11-2025
Revised: 13-12-2025
Accepted: 16-12-2025
Published in Issue 10-02-2026
Published Online: 27-12-2025
Copyright (c) 2025 Ahmed Awad Nasser, Masoud Allame, Habeeb Abed Kadhim Aal-Rkhais, Majid Tavassoli Kajani (Author)

This work is licensed under a Creative Commons Attribution 4.0 International License.
How to Cite
Abstract
The obstacle problem is a nonlinear variational inequality, first introduced to model contact phenomena in solid mechanics. Because of the singularity of the solution along the free boundary, the development of accurate and efficient numerical methods is critical. This paper introduces a novel meshless technique for numerically solving the obstacle problem, utilizing the local radial basis function-finite difference (lRBF-FD) method. An active set strategy is combined with the lRBF-FD method to manage the complementarity condition of the problem. Notable advantages of this method are its independence from any mesh and its straightforward implementation with high numerical stability.
Keywords
- Obstacle problem,
- Active set method,
- radial basis functions,
- meshfree method,
- Finite difference method
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10.57647/ijm2c.2026.1603.17
