Collaborative Research: RUI: Three-Dimensional Multiphysics Simulation of Multi-phase Flows with Magnetic Fluids

铁磁流体（对磁场有反应的工程流体，具有许多成熟的工业应用）的合成进展增加了这些流体在新领域的潜在应用范围。铁磁流体的新兴应用包括：药物的磁性靶向，生物医学系统中的细胞分选和磁性驱动的污染物去除。在这些应用中，铁磁流体的使用使依赖于使用磁场“远程控制”铁磁流体的新技术成为可能。然而，这些技术的实现受到这些系统的复杂仿真的阻碍，以供进一步开发和设计。拟议的研究计划包括开发有效的、健壮的计算工具，以实现这种模拟。特别是，计算代码将包括铁磁流体的特殊磁性物理以及由磁场产生的力，这些力在这些应用中作为控制手段。这些有效的仿真工具的开发将支持和加速这些新兴技术的创新。此外，拟议的代码开发、模拟和综合物理实验方案将作为概念验证，为复杂的科学和工程应用纳入现实的多物理场流体模拟。拟议的研究项目将涉及前沿研究的本科生和硕士生，包括在STEM学科中代表性不足的群体成员，如女性和第一代大学生。在磁性药物靶向中，其组成纳米颗粒已被功能化以携带治疗药物的铁磁流体被定向到肿瘤或其他局部部位（例如，在眼睛中）；将（非磁性）生物细胞浸在铁磁流体中分选，使施加磁场的力取决于细胞的大小；通过将污染物吸附到磁性纳米颗粒上来净化被污染的流体，然后通过磁力将其从流体中分离出来。然而，这些应用的进展受到流体动力系统的复杂性、多尺度和多物理性质的阻碍。特别是，由于当代流体动力学代码没有设计成包含磁流体系统的附加物理，因此用这些代码进行有效的模拟是困难的。该提案描述了一项计划，旨在开发和测试一种新的并行、多相的全三维流动代码。该项目将导致灵活和高效，多相磁流体模拟代码，是完全三维和并行的高性能计算。因此，该代码将支持与所处理的重要应用程序相关的逼真模拟。具体来说，为了处理上述应用，代码将对铁磁流体和其他流体之间具有动态界面的流动进行建模和模拟。此外，代码将以灵活的方式实现粘度效应（磁粘度）以及由施加磁场（磁泳）产生的驱动力的模型，简化了模型的调整和更新。

Advances in the synthesis of Ferrofluids (engineered fluids that respond to magnetic fields and have a number of well-established industrial applications) have increased the scope of potential applications of these fluids to new areas. Emerging applications of ferrofluids include: magnetic targeting of drugs, cell sorting in biomedical systems and magnetically driven contaminant removal. In each of these applications the use of ferrofluids enables new techniques that depend on the use of magnetic fields for 'remote control' of the ferrofluid. However, the realization of such technologies is hampered by complexities simulation of these systems for further development and design. The proposed research program includes the development of effective, robust computational tools that will enable such simulations. In particular, the computing codes will include the particular magnetic physics of ferrofluids as well as the forces resulting from the magnetic fields, which serve as the means of control in these applications. The development of these effective simulation tools will support and accelerate innovation in these emerging these technologies. Moreover, the proposed program of code development, simulations and integrated physical experiments will serve as a proof-of-concept for the inclusion of realistic multiphysics fluid simulations for complex scientific and engineering applications. The proposed research program will involve undergraduate and masters-degree students in leading-edge research, including students who are members of groups under-represented in STEM disciplines such as women and first-generation college students.In magnetic drug targeting, a ferrofluid whose constituent nanoparticles have been functionalized to carry theraputic drugs is directed to a tumor or other localized site (e.g., in the eye); sorting of(nonmagnetic) biological cells by immersion in a ferrofluid so that the force of an applied magnetic field depends on cell size; purification of a polluted fluid by adsorbption of contaminants to magnetic nanoparticles, which are then separated from the fluid by magnetic forces. However, advances in these applications are stymied by the complex, multi-scale and multi-physics nature of the fluid-dynamical systems in which they occur. In particular, because contemporary fluid-dynamics codes are not designed to incorporate the additional physics of magnetic-fluid systems, effective simulation with these codes is difficult. The proposal describes a plan to develop and test a new parallel, multi-phase code for fully three-dimensional flows. This project will lead to a flexible and efficient, multi-phase magnetic-fluid simulation code that is fully three-dimensional and parallelized for high-performance computing. Hence, the code will enable realistic simulations relevant to the significant applications addressed. Specifically, in order to address the above-noted applications, the code will model and simulate flows with dynamic interfaces between the ferrofluid and other fluids. Moreover, the code will implement models of viscosity effects (magnetoviscosity) as well as driving forces that result from applied magnetic fields (magnetophoresis) in a flexible manner that simplifies adjustment and updating of the models.