Advances in technology and engineering require innovative approaches that often involve systems more complex than their predecessors. Increased complexity necessitates more sophisticated measurement techniques in order to understand, quantify, and refine innovative approaches. This is abundantly apparent in fluid flows and mechanical deformations, which are typically 3-dimensional (3D) and may involve highly unsteady or transient behavior. Recent advances in particle imaging and tracking now, for the first time, allow measurement of time-varying 3D particle displacement and velocity within a volumetric region. The objective of this MRI project is purchase of a TSI V3V system capable of 3D (volumetric), 3-component displacement and velocity measurements for use in a range of projects including porous media flows, sea turtle locomotion, investigation of diesel particle collection efficiency in electrostatic precipitators (ESP), optimization of plant-based contaminant remediation, and measurement of plastic deformation fields in 3D sheet metal for assessing mechanical properties and spot weld failure mechanisms.
The TSI V3V system has refined and commercialized the technology used in defocusing digital particle image velocimetry (DDPIV). Specifically, the system extracts the 3D location of imaged particles in a flow or dots on a surface based on their location in the image plane and a quantified measure of how "out-of-focus" they are. Then comparing particle positions obtained from successive images using particle tracking techniques, particle displacements and, when divided by inter-frame delay, velocities may be obtained. Particle positions anywhere within a designed volumetric field of view (FOV) may be triangulated, so the results are truly volumetric and 3D. Currently available fast data transfer systems allow for capture of image sequences so that time-varying data may be obtained as well. Finally, the self-contained, single imaging plane configuration makes measurements relatively easy, even in settings where much/most of the experiment is optically inaccessible. As such, the V3V system is ideal for providing essential 3D velocity and displacement information in a wide range of existing and future projects.
Intellectual Merit. Purchase of the V3V system will provide an unprecedented capability in volumetric, 3-component measurement of complex flow and mechanical deformation phenomena. This capability will provide essential information for understanding the ecology of an endangered species (sea turtles), refining and optimizing methods for maintaining air and water quality, and understanding the properties and failure mechanisms of alloys used in automobile manufacturing. Application of the V3V system to these areas will also involve efforts to improve the system capability including increasing the accuracy of displacement measurements by borrowing from image correlation analysis tools developed for 2D mechanical deformation measurements and adjusting the FOV of the system for increased resolution using a specialized optical setup. Both approaches promise to improve the results of the current projects and promote application of the purchased V3V system to a wider range of research areas.
Broader Impacts. The V3V system will be utilized by two departments (Mechanical Engineering and Environmental and Civil Engineering) on research spanning several disciplines (engineering, biology, and chemistry). The broad utilization of the V3V system will bring together PIs, graduate students, and undergraduates from these diverse disciplines. Moreover, the combination of a state-of-the-art measurement system with novel and highly relevant research topics such as endangered species, air quality, and plant-based contaminant remediation promises to attract new students and underrepresented groups to research. Outreach will be further enhanced by showcasing the research projects and results in public settings such as "Science Day at the Zoo," an event organized by the Dallas Zoo and Aquarium to promote science education in the local community and continuing education for K-8 teachers in the Dallas-Ft. Worth Metroplex.
