Modeling and Computation of Flow-Structure Interaction in Multi-Phase and Complex Fluids

塞尼塞罗斯 研究者和合作者发展了两类现代的混合数值方法来研究二维和三维多相流的流固耦合问题。混合计算方法融合了两组通常不相交的方法，（通过水平设置方法和通过基于相场的模型）和前沿跟踪（浸入边界设置），另一方面移动网格和自适应网格细化，以产生一种有效的方法，利用每种方法的最佳功能。 此外，控制自适应前端跟踪inconcert与领先的小尺度半隐式时间离散化被用来克服长期存在的时间步长问题（刚度）与界面张力，所有这些成分的混合产生完全adaptiveand非刚性的混合方法准确地捕捉small-scaleeffects，高界面变形，以及多相流和复杂流中的流-结构相互作用。 了解流动-结构相互作用对多相流宏观行为的影响具有重要的理论意义和实际意义。 表面活性剂、粘弹性纤维、流体界面以及聚合物微结构和纳米结构可以从根本上改变流体的行为，并最终决定复杂软物质配方的性质。 该方法是一个重要的工具来研究流-结构相互作用的各种问题的直接利益的纳米技术，软材料工业，和一些生物医学应用。 该项目还服务于一个重要的教育目标：本科生和研究生的跨学科教育和培训。

Ceniceros The investigator and collaborators develop two classes ofmodern, hybrid numerical methods to study fluid-structureinteraction for multi-phase flows in two and three dimensions.The hybrid computational methodologies merge two sets of usuallydisjoint approaches, front capturing (both through the level setmethod and through phase field based models) and front tracking(immersed boundary setting) on one hand, and moving meshes andadaptive mesh refinements on the other, to produce an efficientmethod that exploits the best features of each individualapproach. In addition, controlled adaptive front-tracking inconcert with a leading small-scales semi-implicit timediscretization is used to overcome the long-standing timestepping problem (stiffness) associated with interfacial tension.The blending of all these ingredients produces fully adaptiveand non-stiff hybrid methods for capturing accurately small-scaleeffects, high interfacial deformations, and flow-structureinteraction in multi-phase and complex flows. The understanding of how flow-structure interactioninfluences the macroscopic behavior of multi-phase flows is ofboth fundamental and practical significance. Surfactants,viscoelastic fibers, fluid interfaces, and polymericmicrostructures and nanostructures can radically change thebehavior of a flow and ultimately determine the properties ofcomplex soft matter formulations. The methodologies are animportant tool to study flow-structure interaction for a widevariety of problems of direct interest to nanotechnology, thesoft materials industry, and to some biomedical applications. Theproject also serves an important education goal: theinterdisciplinary education and training of undergraduate andgraduate students.