This research is devoted to understanding the physical mechanism of cavitation erosion in liquid flows at the fundamental scale of cavitation bubble collapse. Cavitation bubbles form in a liquid when the pressure of the liquid decreases locally below the saturated vapor pressure $p_v^{sat}$. The bubbles grow due to low ambient pressure and collapse when the surrounding liquid pressure increases again above $p_v^{sat}$. Bubble collapse near solid walls can result in high velocity liquid jet and shock wave emission that cause high pressure loads on the wall. These pressure loads are responsible for the erosive damages on solid surfaces, as observed in applications like liquid fuel injection, hydrodynamic power generation and marine propulsion. On the other hand, the pressure loads from collapsing bubbles are exploited for applications like shock wave lithotripsy, drug delivery and cleaning surfaces. In this work, we follow a numerical approach, which begins with the development of a compressible solver capable of resolving the cavitation bubbles in the finite-volume code YALES2¹ employing a simplified homogeneous mixture model. The solid material response to cavitation loads is resolved with the finite element code Cast3M². A one–way coupling approach for fluid–structure interaction (FSI) simulation between the fluid and solid domains is pursued. In this simple approach, the pressure field computed by the fluid solver at the fluid–solid interface is communicated to the solid solver which computes the deformation induced in the material. In the end, the dynamical events responsible for surface deformation are highlighted from 2D vapor bubble collapse dynamics and associated pressure loads on the solid wall are estimated. The response of different materials to bubbles collapsing at different distances from the solid wall is discussed.

本研究致力于在空化气泡破裂的基本尺度上了解液体流中空化侵蚀的物理机制。当液体的压力局部降低到低于饱和蒸气压时，在液体中会形成空化气泡${磷}_v^{秒\mathrm{一种}吨}$. 气泡因环境压力低而增长，当周围液体压力再次增加时，气泡会破裂${磷}_v^{秒\mathrm{一种}吨}$. 固体壁附近的气泡破裂会导致高速液体射流和冲击波发射，从而在壁上造成高压载荷。正如在液体燃料喷射、流体动力发电和船舶推进等应用中所观察到的那样，这些压力载荷是造成固体表面侵蚀损坏的原因。另一方面，来自破裂气泡的压力载荷被用于冲击波碎石术、药物输送和清洁表面等应用。在这项工作中，我们采用数值方法，首先开发可压缩求解器，该求解器能够使用简化的均质混合模型解决有限体积代码 YALES2 ^{1 中}的空化气泡。固体材料对空化载荷的响应用有限元代码 Cast3M 解决² . 正在寻求一种用于流体和固体域之间的流固耦合 (FSI) 模拟的单向耦合方法。在这种简单的方法中，由流体求解器在流体-固体界面处计算出的压力场被传送到固体求解器，后者计算材料中引起的变形。最后，从二维汽泡坍塌动力学中突出显示了导致表面变形的动力学事件，并估计了实体壁上的相关压力载荷。讨论了不同材料对气泡在距实体壁不同距离处坍塌的响应。