A vast number of natural and man-made materials are solids that contain pores (voids), for example rocks, soil, biological tissues, cements, ceramics, etc. These porous media are used in many areas of applied science and engineering including filtration, soil mechanics, petroleum engineering, bioengineering, etc. The static properties of porous media have been studied intensively for many decades, but the understanding of dynamic interactions of fluids with porous media remains an important area of investigation that can yield critical and much-needed improvements to applications in health care, environment, and various other areas of engineering. The challenges in this area arise from the complex internal structure of a porous medium, together with the highly nonlinear dynamic behavior of fluids. The proposed activity involves the construction of a carefully conceived experimental apparatus that facilitates precise and repeatable experiments involving (dynamic) vortex flows and porous media. Key difficulties are addressed, firstly by a high-precision vortex generator devised in the PI's lab that is controlled by a computer, whose software is also developed in-house. This will allow the generation of a variety of velocity profiles for the fluid to an unprecedented level of precision. Secondly, a synthetic porous medium will be constructed whose optical refractive index is matched to the fluid, thus making it transparent and allowing observation and measurement of the flow by planar laser-induced fluorescence. Intellectual Merits of the proposed activity involves the investigation of fundamental scientific questions regarding vortex flows in porous media, namely uncovering the effect of (a) porosity, (b) permeability, (c) fluid density and viscosity, (d) injection velocity, pressure, pulse duration, and frequency on the behavior of fluid pattern separation, accumulation, and transport phenomena of vortex flow within the porous medium. This research is well motivated by preliminary results and will be conducted with a new and unique experimental setup for measurements and visualization of vortex flows in porous media. The interaction of vortex flows with porous media and their transport through porous media is a new direction that can potentially be transformative. Broader Impacts: This proposal benefits the society by contributions to the advancement of many processes and devices that are critically important to our well being due to their effect on healthcare (biomedical devices), the environment (underground flows), and agriculture (erosion, grain drying and conditioning), among others. The results of this research will be widely disseminated through the web, via conferences, as well as seminars. This research will be integrated with educational activities via new courses, by providing research opportunities for undergraduates in their required (capstone) design projects, as well as K-12 outreach via collaboration with HI-TECCC (High-Technology Education Coalition of Collin County). The proposed activity includes a carefully crafted broadening participation plan that has two main components: one targeting individuals with disability, and the other targeting under-represented minorities and women. The PI has created an accessible lab environment and has collaboration with UTD Office of Accessibility to make research positions available to disabled students. The PI also has an active, consistent, and successful track record in recruiting, retaining, and graduating female and minority students.
