基于势流理论建立水下爆炸气泡运动三维模型,采用边界积分法求解拉普拉斯方程,得到气泡的变形及位置,并在计算过程中引入弹性网格技术。避免了因网格扭曲而导致的数值发散,进而模拟了刚性壁面附近三维气泡的动态特性。在数值模拟过程中,将本文计算值与实验数据进行对比分析,结果表明,计算值与实验数据吻合良好。在此基础上,分别模拟了弱浮力、强Bierknes力,强浮力、弱Bjerknes力以及浮力与Bjerknes力相当时壁面附近气泡的运动特征,并将各种工况的计算结果与基于开尔文冲量理论(Kelvin Impulse)的Blake准则进行对比分析与讨论,得到了不同参数下气泡的运动特征。
The dynamics of three-dimensional bubble near a rigid wall is investigated in this paper. Based on potential-flow theory, the model of three-dimensional bubble is created, and Laplace equation is solved by boundary integral method, obtaining the deformation and location of bubble. Elastic mesh technique is adopted in computing process to avoid the numerical divergence caused by mesh grid distortion. The comparison between three-dimensional model and experimental data indicates that the calculated results coincide well with the experimental data. The dynamics of bubble near a rigid wall when the weak buoyancy is relative to strong Bjerknes force, the strong buoyancy is relative to weak Bjerknes force, and the buoyancy is relative to Bjerknes force are simulated by the three-dimensional model respectively. The calculated result of each case is discussed and compared with the Blake criterion which is based on Kelvin Impulse theory, obtaining the dynamic characters of bubble in different parameters.