Abstract
Block-structured mesh generation offers significant advantages in numerical computation and simulation, yet conventional methods often rely on manual intervention, struggling to balance automation with high-quality output. To address this, an automated block-structured mesh generation framework that integrates deep reinforcement learning and optimal conformal mapping techniques is proposed in this paper. This framework utilizes the triangulation of the geometric model as input and operates in the following four steps. Firstly, surface triangular meshes are mapped to planar parametric domains using the Ricci flow algorithm. Secondly, isocontours are extracted based on density variation before and after conformal mapping to guide partitioning. Thirdly, a reinforcement learning decision framework is constructed to formulate mesh generation as a sequential decision-making process, where topological template selection and singularity placement are optimized through reward functions. Finally, surface-structured meshes are generated through mesh smoothing and inverse conformal mapping. Experimental results demonstrate that the proposed method outperforms existing methods in both generation efficiency and mesh quality, providing an intelligent new solution for automated mesh generation in CAD/CAE applications.
















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Acknowledgements
We extend our gratitude to the anonymous reviewers for their meticulous evaluation and for offering insightful and comprehensive feedback. We also gratefully acknowledge the Grid Generation Team at the Computational Aerodynamics Institute of CARDC for their essential support during manuscript preparation.
Funding
This work is partially supported by the National Key R & D Program of China under Grant No. 2023YFB3309100, “Pioneer” and “Leading Goose” R & D Program of Zhejiang Province (No. 2025C01086), the National Natural Science Foundation of China under Grant No. U22A2033.
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L.Q. and Q.W. wrote the main manuscript text, coding, and prepared all the figures, R.M. developed and validated the code for conformal parameterization, J.Q., Y.L., J.X. and R.G. checked and modified the manuscript grammar, G.X. designed the manuscript framework and revised the overall content. Y.P. provided technical guidance for the manuscript and designed the experiments. All authors reviewed the manuscript.
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Qi, L., Wu, Q., Xu, G. et al. DRL-MeshGen: automated block-structured mesh generation framework via deep reinforcement learning and optimal conformal mapping. Engineering with Computers 41, 4293–4315 (2025). https://doi.org/10.1007/s00366-025-02199-9
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DOI: https://doi.org/10.1007/s00366-025-02199-9
