近复杂几何固壁空泡溃灭的伪势格子Boltzmann建模*

格子Boltzmann方法伪势多相模型具有高效性和复杂几何边界实施的简易性。该文采用改进作用力的伪势多相模型,通过优化参数实现最大程度的热力学一致性,进而提高模型的密度比和稳定性。分别从伪速度、网格不变性、Young-Laplace验证等方面研究了改进模型的性能。通过改进的模型模拟了复杂几何固壁附近空泡溃灭过程。分析了空化泡溃灭阶段的密度场、压力场和速度场演化过程,以及复杂几何固壁附近的空泡动力学特性。结果表明伪势格子Boltzmann方法在探索空泡溃灭和复杂几何固壁间的相互作用规律研究中是一种有效的工具。

Modeling for collapsing cavitation bubble near complex geometry solid wall by improved pseudopotential lattice Boltzmann model

The pseudopotential multi-phase model of the lattice Boltzmann method(LBM) is used to study the collapsing cavitation bubble near complex geometrical solid wall. In this paper, an improved forcing scheme, which can achieve thermodynamic consistency by optimizing related parameters, is adopted to improve density ratio and stability. The performance of the improved pseudopotential multi-phase model is studied from three aspects: the spurious current, the independence of grid and the verification of the Young-Laplace law. The cavitation bubble collapse near complex geometrical solid wall is modeled by the improved the pseudopotential multi-phase LBM. Meanwhile, the density field, pressure fields and velocity field evolution process of cavitation bubble collapsing stage are analyzed, as well as the dynamic characteristics of the cavitation bubble collapsing near complex geometrical solid wall. The results show that the pseudopotential multi-phase LBM is an effective tool to investigate the interaction between the collapsing bubble and complex geometrical solid wall.