MRI: Development of a Spatiotemporal Velocimetry with Simultaneous Size Measurements for Polydispersed Multi-Phase Flows

CTS-0521102

P. Vlachos, Virginia Polytechnic Institute

This grant is to develop a unique instrumentation system for spatially resolved, simultaneous velocity and particle size measurements in polydispersed multi-phase flows with kHz temporal resolution. The system will be used in biofluid mechanics, environmental hydraulics, and turbomachinery flows. These seemingly unrelated areas of fluid mechanics share the fundamental need to address unanswered questions relating the fluid motion along with the motion of polydispersed particulates in anisotropic flows that are governed by turbulence or unsteadiness encompassing a wide range of flow scales and structures. Existing instrumentation fails to deliver spatio-temporally resolved measurements with sufficient sampling frequency to capture turbulent fluctuations while simultaneously measuring the particulate size and size distribution. The new Time Resolved Digital Particle Image Velocimeter (TRDPIV) instrumentation will deliver hardware and algorithm advancements to overcome the experimental challenges present in polydispersed multiphase flow measurements. The new system combines the advantages of conventional DPIV to spatially resolve a flow with the advantages of Laser Doppler Velocimetry or hot-wires to measure high frequency velocity fluctuations and the advantages of Phase Doppler Particle Anemometry to measure particle sizes. The instrumentation developed under this grant will have a direct and broad impact upon the experimental fluid mechanics community. Multi-phase flows such as particle transport and collision, coagulation, flotation, spray atomization and bubble dynamics are present in a wide variety of industries such as chemical, aeronautical/aerospace, naval, power generation, automotive and biomedical. A new unique measurement capability will be available to researchers and engineers in all these areas thus having an indirect yet very broad impact on the nation's industrial, and research infrastructure. Broad and direct impact on diversity will be achieved through well-focused efforts to promote undergraduate and graduate research in recruiting underrepresented women and minorities. Educational impact will be achieved through thorough training and mentoring of graduate and undergraduate students that will be developing and using the proposed system. The broader educational impacts will extend to the graduate and undergraduate classrooms where the system will be used for teaching advanced experimental methods and performing demonstrations in our required fluid mechanics courses.