两相界面流是一种十分复杂的物理现象，如何实现其界面的精细捕捉及高效求解一直是数值模拟领域的难题之一。申请人针对两相界面流，在国际上首次提出了界面捕捉方法VOSET和速度压力耦合算法IDEAL，得到国内外学者认可、推广和应用，但已有研究仅面向简单几何结构和直角正交网格系统，很难适用于不规则复杂区域。随着所研究问题日益复杂化，几何结构不断趋于复杂多样，网格数量通常高达百万或千万，这对界面捕捉精度和计算收敛速度提出了新的挑战。据此，本项目将针对复杂区域两相界面流，基于适体网格系统：（1）建立精确的界面捕捉方法VOSET；（2）发展高效的非稳态速度压力耦合算法IDEAL；（3）提出耦合动态自适应网格的新型多重网格技术。最终通过以上三个方面的研究，构建复杂区域两相界面流的精确高效计算体系，该计算体系一方面在保证质量守恒的前提下实现相界面的精确捕捉和表面张力的精确计算，另一方面收敛速度提高10倍以上。

The two-phase interfacial flows are complicated physical phenomena. How to efficiently solve the interfacial flows and accurately capture their interfaces has always been one of the biggest challenges in numerical simulation field. Recently, an interface capturing method VOSET and a velocity-pressure coupled algorithm IDEAL were firstly proposed by the present applicant for the interfacial flows, and have been accepted, extended and applied by domestic and overseas scholars. However, all of these researches are only for the simple geometrical structure and orthogonal Cartesian grid system. With the increasing complex of research problems, the geometric structures constantly tend to be more complicated and their grid numbers are usually up to million or ten million, leading to new challenge for the accuracy and convergence rate. The present project focuses on the two-phase interfacial flows in complex regions and the major research contents are as follows. Based on the body-fitted grid system, (1) build the accurate interface capturing method VOSET; (2) develop the efficient unsteady velocity-pressure coupled algorithm IDEAL; (3) propose a new multigrid technique with dynamically adaptive grid. Through these researches, an accurate and efficient calculation system will be constructed and its convergence rate will increase above 10 times than the traditional.