The accuracy of meshless methods like Smoothed Particle Hydrodynamics (SPH) is highly dependent on the quality of the particle distribution. Existing particle initialization techniques often struggle to simultaneously achieve adaptive resolution, handle intricate boundaries, and efficiently generate well-packed distributions inside and outside a boundary. This work presents a fast and robust particle initialization method that achieves these goals using standard SPH building blocks. Our approach enables simultaneous initialization of fluid and solid regions, supports arbitrary geometries, and achieves high-quality, quasi-uniform particle arrangements without complex procedures like surface bonding. Extensive results in both 2D and 3D demonstrate that the obtained particle distributions exhibit good boundary conformity, low spatial disorder, and minimal density variation, all with significantly reduced computational cost compared to existing approaches. This work paves the way for automated particle initialization to accurately model flow in and around bodies with meshless methods, particularly with SPH.

翻译：无网格方法（如光滑粒子流体动力学，SPH）的精度高度依赖于粒子分布的质量。现有的粒子初始化技术通常难以同时实现自适应分辨率、处理复杂边界以及在边界内外高效生成紧密堆积的分布。本文提出了一种快速鲁棒的粒子初始化方法，该方法利用标准SPH构建模块实现了上述目标。我们的方法能够同时初始化流体与固体区域，支持任意几何形状，并能在无需表面粘合等复杂流程的情况下获得高质量、准均匀的粒子排布。在二维与三维场景中的大量实验结果表明，所获得的粒子分布具有良好的边界贴合性、低空间无序度及最小的密度变化，且与现有方法相比计算成本显著降低。这项工作为实现自动化粒子初始化以精确模拟无网格方法（尤其是SPH）中物体内部及周围的流动铺平了道路。