Collaborative Research: MSPA-MCS: Simulation and Visualization of Flow at Interfaces

University Of North Carolina At Chapel Hill, Chapel Hill NC

Investigators

Abstract

Simulation and Visualization of Flow at Interfaces Abstract A wide variety of important phenomena in fluid dynamics involve the changes of the boundary between two fluid regions. Such fluid phenomena include the instabilities in two-fluid flows, the evolution of the boundary between clear and particle-laden liquids, and the behavior of the boundary between air and water. This research uses computer simulations to study such interfaces between fluids together with new methods of creating images from these simulations in order to allow researchers to gain a better understanding of the fluid behaviors. Better simulation and visualization of flow interfaces will advance scientific understanding and aid in engineering design. Areas of broader impact include the design of self-propelled micromachines for medicine, surface-transported pollution analysis and control on rivers, and controlling droplet formation for ink-jet printers. This project is also advancing education by training student, hiring minority students for summer internships, developing courses on visualizing fluid simulations for the research community, and distributing code and data on the web. This research begins with the modification of existing numerical simulation codes for several different classes of interfacial flows. The specific scientific phenomena that are simulated and visualized in this research includes: instabilities in the sedimentation of particle-laden regions into clear fluids, including the analogue of the Rayleigh-Taylor instability; the development of fluid braids and other structures due to surface tension effects at contact lines; the internal splashes of solid particles falling through fresh/salt-water interfaces; and locomotion of simple articulated figures and other micro- and nano-scale mechanisms for swimming through viscous fluid. Using the data from the simulations, new methods of visualizing the flow at interfaces are tailored to each phenomena utilizing various techniques including surface creation from particles, identification and tracking of critical points in 3D flows, streamline placement, and anisotropic lighting for simulated rheoscopic fluid suspensions.