随着国防、经济以及工业的发展，空化研究在很多领域都展现出了重要价值，在导弹出水、水下航行器的运行以及新型医疗器械的开发中都具有指导作用。空化是指在液体内部局部压力低于饱和蒸汽压时发生的相变现象，其关键过程是泡群的初生、发展和溃灭。气泡在复杂边界附近运动时会产生非球形变形并导致高速射流的产生，气泡快速脉动还会诱发高强度的压力波，这两个因素使得气泡具有很强的“破坏性”。高精度数值模拟显示，泡群运动具有更复杂的特征。时间特征上，泡群的周期相对单气泡的周期更长；压力特征上，泡群中心气泡的溃灭压力相对单气泡的溃灭压力存在明显的增幅。此外，泡群的溃灭表现出由外向内的特征，这个过程伴随着能量的传递和聚焦。本文旨在通过数值仿真和理论分析研究气泡相互作用中的能量传递规律，以深入分析泡群溃灭压力的形成机理并提高其定量预测精度。具体研究包括以下几个方面：

（1）双泡能量传递研究。辐射($\alpha$)-接收($\beta$)结构能量传递模型是泡群能量传递模型的基础，通过量纲分析确定两个主要的无量纲参数为无量纲距离和初始能量比，本文重点研究了这两个参数对能量传递率以及相对射流能量的影响。结果表明，当两个气泡初始半径完全相等时，随着无量纲距离以及初始能量比的增加，能量传递率$\varepsilon$呈现下降趋势。当无量纲距离增大时，两泡间的相互作用减弱，相对接收能量与无量纲距离间满足关系：$\varepsilon  \propto \frac{1}{d^2}$。而当初始能量比增加时，$\beta$泡内最大压力先增加后减少，相对射流能量与初始能量比的关系为：$J  \propto \psi$。

（2）泡群能量传递研究。考虑到泡群溃灭过程中存在层层传递和向内聚焦的特征，本文提出了直链式泡群能量传递模型和聚焦式能量传递模型。直链式泡群模型由一个辐射能量的气泡（$\alpha$）以及若干接受能量的气泡（$\beta$）所构成，并且它们在同一条直线上。通过改变无量纲距离来分析直链式泡群的能量传递规律。结果表明，随着无量纲距离的增大，相对接收能量在下降。在保持无量纲距离的情况下，增加$\beta$泡的数量，发现幅射泡接收到的能量只和接收泡所处的位置有关。聚焦式泡群由若干个辐射能量的气泡（$\alpha$）和一个接受能量的气泡（$\beta$）所构成，其中$\alpha$泡分布在$\beta$泡附近。本文基于势流理论与能量守恒定律，间接得到周围气泡给中心气泡传递的能量与无量纲距离间的关系。随后对三类基础泡群和其复合泡群进行了仿真计算。数值结果表明，随着无量纲距离的增大，相对传递能量在减小，这与理论模型预测结果一致。在此基础上，进一步分析了复合结构能量传递与基本结构间的能量传递关系，得到了叠加关系。最后，对聚焦式泡群的压力特征进行分析，再次观察到了压力的增幅效应以及中心气泡溃灭时压力峰值出现的时间滞后现象。

（3）带相变三相流固耦合软件的开发与测试。开发内容主要集中于overcompressibleThreephaseChangeInterFoam模块的实现，采用三维圆柱入水的算例对软件的精度进行验证，通过测试结果来优化求解器的算法。经多轮测试，目前本软件已经可以精确捕捉到液面的变形以及闭合情况，圆柱的运动与实验的误差也保持在5\%以内。

The study of cavitation has significant value in many fields, including defense, economy, and industry, guiding the operation of missile launches, underwater vehicles, and the development of new medical equipment. Cavitation refers to the phase transition phenomenon that occurs when the local pressure inside a liquid is lower than the saturation vapor pressure, and its key process is the birth, development, and collapse of bubble clusters. When bubbles move near complex boundaries, it can produce non-spherical deformations and generate high-speed jets, and rapid pulsation of bubbles can also induce high-intensity pressure waves, making bubbles highly "destructive". High-precision numerical simulations show that bubble cluster motion has more complex features. In terms of time characteristics, the period of bubble clusters is longer than that of a single bubble; in terms of pressure characteristics, the collapse pressure of the center bubble in the cluster is significantly higher than that of a single bubble. In addition, the collapse of bubble clusters shows an outward-to-inward feature, accompanied by energy transfer and focusing. This paper aims to study the energy transfer law in bubble interactions through numerical simulations and theoretical analysis, to deeply analyze the formation mechanism of bubble cluster collapse pressure and improve its quantitative prediction accuracy. Specific research includes the following aspects:

(1) Study of energy transfer between two bubbles. The radiation ($\alpha$-bubble)-receiving ($\beta$-bubble) transfer model of the structure is the basis of the bubble clusters energy transfer model. Two main dimensionless parameters, namely dimensionless distance and initial energy ratio, are determined by dimensional analysis. This study focuses on the effect of these two parameters on energy transfer rate and relative jet energy. The results show that when the initial radii of the two bubbles are exactly the same, the energy transfer rate $\varepsilon$ decreases as the dimensionless distance $d$ and the initial energy ratio $\psi$ increase. As the dimensionless distance increases, the interaction between the bubbles weakens, and the relationship between the relative received energy and the dimensionless distance is $\varepsilon \propto \frac{1}{d^2}$. When the initial energy ratio increases, the maximum pressure inside the $\beta$-bubble first increases and then decreases, and the relationship between the relative jet energy and the initial energy ratio is $J \propto \psi$.

(2) Study on energy transfer in bubble clusters. Considering the characteristics of layered transfer and inward focusing during the collapse of bubble clusters, this paper proposes a linear chain model and a focusing energy transfer model. The linear chain model consists of a radiating bubble ($\alpha$) and several receiving bubbles ($\beta$) on the same line. The energy transfer law of the linear chain model is analyzed by changing the dimensionless distance. The results show that the relative energy received by the bubbles decreases with the increase of the dimensionless distance. When keeping the dimensionless distance constant, increasing the number of $\beta$ bubbles, it is found that the energy received by the radiating bubble only depends on the position of the receiving bubble. The focusing bubble cluster consists of several radiating bubbles ($\alpha$) and a receiving bubble ($\beta$), with $\alpha$ bubbles distributed near the $\beta$ bubble. Based on potential flow theory and energy conservation law, the relationship between the energy transferred from the surrounding bubbles to the central bubble and the dimensionless distance is indirectly obtained. Then, simulation calculations are carried out on three types of basic bubble clusters and their composite bubble clusters. The numerical results show that the relative energy transferred decreases with the increase of the dimensionless distance, which is consistent with the theoretical model prediction. Based on this, the energy transfer relationship between the composite structure and the basic structure is further analyzed, and the superposition relationship is obtained.

(3) Development and testing of software for three-phase flow solid coupling with phase change. The main focus of development was on implementing the overcompressibleThreephaseChangeInterFoam module. Validation of the software's accuracy was performed using a three-dimensional cylindrical water-entry case, and the solver's algorithm was optimized based on the test results. After multiple rounds of testing, the software is now capable of accurately capturing the deformation and closure of the liquid surface, with cylinder motion error within 5\% of experimental measurements. Finally, an analysis of the pressure characteristics of the focused bubble cluster revealed the amplification effect of pressure and the time lag phenomenon of the pressure peak appearing after the collapse of the central bubble, which was observed again.