Grant: Research Tools and Instruments

The focus of the proposed research is quantitative imaging of complex, two-phase flows that occur in a wide range of engineering applications, including cavitation of marine propellers, flow-induced vibrations and bubble impact dynamics. These applications are characterized by highly three-dimensional, multi-phase (gas-liquid) flows, which present formidable challenges in terms of computational modelling and experimental characterization. We aim to provide insight into the underlying physics of acoustic noise emissions from ships and to develop a set of tools that facilitate the numerical prediction of underwater radiated noise from cavitating marine propellers. In addition to advancing quiet marine technology, our group conducts research in a broad range of fundamental projects involving multiphase flows. The results of this research will be used for mitigation of the environmental impacts of marine transportation, development of novel bioprinting technology, improve safety and efficiency of steel manufacturing and develop sustainable urban infrastructure. Quantitative flow imaging techniques, including particle image velocimetry (PIV), have been implemented at the Fluid Mechanics Laboratory at UVic to obtain global, quantitative flow patterns that lead to improved understanding of the fluid flow. While this image-based approach provides substantial insight into the flow physics, a significant limitation of the present experimental system is that the existing optical instrumentation high-speed camera is dated and cannot achieve either the spatial resolution or the frame rate required for obtaining quantitative insight into the phenomena under investigation. This limitation puts a severe restriction on the scope of experimental projects that we can undertake and on the range of applicability of our present results, because an increasingly wide range of scientific and engineering applications require a higher degree of time resolution to properly visualize and quantify the two-phase phenomena. One of the approaches to reconstructing the dynamically-changing bubble shape involves video recording of the backlight-illuminated flow from several viewing directions using high-speed cameras, which is generally referred to as tomographic shadow imaging. Without the capability to accurately measure the multi-phase interactions at higher speeds, our research group must rely on simplifying assumptions about the multi-phase flow behavior, which limit the applicability of the results. The requested equipment will include an high-speed digital camera, which will provide new experimental capabilities and expand the range of practical applications of the current research undertaken by the applicant. The research that will be enabled by the requested equipment presents significant opportunity for the training of graduate students in various aspects of design of engineering systems as well as in application of the state-of-the-art experimental techniques.