A modified apparent viscosity approach has been implemented for a weakly compressible SPH scheme for two-phase flows where a nonlinear phase must yield under erosive dynamics but also maintain a pseudosolid behaviour under the right conditions. The final purpose is to provide a means to model both dam-break dynamics and erosive interactions between different phases simultaneously while also keeping smooth pressure fields in spite of discontinuities introduced by viscosity variations of a nonlinear phase along with significant differences in mean density. Key contributions include purposeful avoidance of nonphysical elastic behaviour and the integration of a specific particle shifting technique that allows for proper replication of erosion and scouring. In this work, the method is validated by applying it to model a silted-up dam that collapses over a static water bed, effectively including all main elements of interest. Although the formulation is inherently three dimensional, validation is done by direct comparison with data from physical experiments of a dominant two-dimensional nature, assuming variable yield stress of medium-grain quartz sand according to the Drucker–Prager equation. Overall results show most of the expected interface dynamics, such as erosion and transportation of the nonlinear phase, sustained piling of the non-yielded volume of silt, and good correspondence of both granular and water surface position with experimental data. Finally, a series of modelling assumptions and implications for future developments are explicitly stated because of their direct impact on stability and versatility for multiphase, nonlinear flows in general.

已针对两相流的弱可压缩 SPH 方案实施了改进的表观粘度方法，其中非线性相必须在侵蚀动力学下屈服，但又在正确的条件下保持伪固体行为。最终目的是提供一种方法来同时模拟不同相之间的溃坝动力学和侵蚀相互作用，同时保持平滑的压力场，尽管非线性相的粘度变化以及平均密度的显着差异引入了不连续性。主要贡献包括有目的地避免非物理弹性行为以及集成特定的粒子移动技术，以允许正确复制侵蚀和冲刷。在这项工作中，通过应用该方法对在静态水床上倒塌的淤塞大坝进行建模来验证该方法，有效地包括所有感兴趣的主要元素。尽管该公式本质上是三维的，但验证是通过直接与主要二维性质的物理实验数据进行比较来完成的，并根据德鲁克-普拉格方程假设中粒石英砂的屈服应力可变。总体结果显示了大部分预期的界面动力学，例如非线性相的侵蚀和迁移、非屈服淤泥的持续堆积，以及颗粒和水面位置与实验数据的良好对应。最后，明确阐述了一系列建模假设和对未来发展的影响，因为它们通常对多相非线性流的稳定性和多功能性产生直接影响。