The NURBS basis is introduced into the boundary element method (BEM) for solving the liquid sloshing problem in the multiply connected domain. An ideal liquid assumed to be inviscid, incompressible is used to study the sloshing characteristics in the cylindrical tanks with barrels of the arbitrary shapes, dimensions and number. Considering the boundary conditions at the free surface and the tank bottom as well as the constant section of the tank, the Laplace equation for potential flow problem can be decoupled into 2D Helmholtz and modified Helmholtz equations. The NURBS widely used in the CAD industry is adopted in this paper to approximate both the boundary geometry and the field variables. The proposed model is verified against the available results from some existing literatures. Meanwhile, the effects of geometric parameters, number and arrangement of internal barrels on liquid sloshing characteristics (such as the sloshing force, surface elevation and natural frequencies) in cylindrical tanks are also investigated in detail. This paper is expected to provide useful guidance for design of cylindrical tanks equipped with several internal tubular structures (such as the fast reactor with pumps and heat exchangers).

将NURBS基础引入边界元方法（BEM）中，以解决多重连通域中的液体晃动问题。使用一种假定为无粘性，不可压缩的理想液体来研究具有任意形状，尺寸和数量的桶的圆柱形罐的晃动特性。考虑到自由表面，储罐底部以及储罐恒定截面的边界条件，可以将潜在流动问题的拉普拉斯方程解耦为二维Helmholtz方程和改进的Helmholtz方程。本文采用在CAD行业广泛使用的NURBS来近似边界几何和场变量。对照一些现有文献的可用结果验证了所提出的模型。同时，几何参数的影响 还详细研究了圆柱桶中内部桶的数量和布置对液体晃荡特性（例如晃荡力，表面高度和固有频率）的影响。有望为具有多个内部管状结构的圆柱形储罐的设计（例如带有泵和热交换器的快速反应器）提供有用的指导。