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Showing 1 to 16 of 16 for “"Time-Resolved Digital Particle Image Velocimetry"”.
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An Investigation of Dolphin-Groove Inspired Surface Patterning on Flow Control
… control with minimal skin friction drag penalty. Time-resolved digital particle image velocimetry (TR-DPIV) was used to track the development of the flow separation within the boundary layer and compared to the smooth plate (non-grooved) wall cases. The grooved surfaces form embedded vortices …
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Investigation of Particle Trajectories for Wall Bounded Turbulent Two-Phase Flows
… more than 40 years of research, operation with a particle-laden inlet flow remains a significant problem for modern turbomachines. The purpose, therefore, is to develop experimental methods for investigating multi-phase flows relevant to the cooling of gas turbine components. Initially, several …
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Wall shear measurements in arterial flows
… and wall shear stress (WSS) levels, as well as particle residence times. The relationship between these hemodynamic parameters and vascular injury response is of great relevance to understanding the cardiovascular disease process. In this work, new methods and algorithms are developed and …
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A Comparative In Vitro Study of the Flow Characteristics Distal to Mechanical and Natural Mitral Valves
… techniques by employing a powerful, high-speed Time-Resolved Digital Particle Image Velocimetry (TRDPIV) system to map the flow field. We compare the flows downstream from a St. Jude Medical bileaflet MHV, a porcine mitral valve (MV), and a combination of both valves to simulate the technique of …
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Turbulent Characteristics in Stirring Vessels: A Numerical Investigation
… (a commercial CFD package) are compared with Time Resolved Digital Particle Image Velocimetry (DPIV) for baseline configurations in order to validate and verify the fidelity of the computations. Different turbulence models are used in this study in order to determine the most appropriate for …
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Development of a Virtual Scientific Visualization Environment for the Analysis of Complex Flows
… First and foremost, the capabilities of our Time-Resolved Digital Particle Image Velocimetry (TRDPIV) system were improved, allowing near-wall wall TRDPIV on compliant, dynamically moving boundaries. As a result, false flow-field vectors due to reflections from the boundary walls were …
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Multiphase Hydrodynamics in Flotation Systems
… turbulence experiment was conducted to verify particle collision models. The slip velocities of solid particles and bubbles were measured using Digital Particle Image Velocimetry (DPIV). The experimental results were compared with the predictions from empirical and theoretical collision models. …
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Geometry induced flow disturbances
… endothelialization. The first study employed time-resolved Digital Particle Image Velocimetry (DPIV) to compare the hemodynamic performance of two stents in a compliant vessel. The first stent was a rigid insert, representing an extreme compliance mismatch. The second stent was a commercially …
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Passive Turbulent Boundary Layer Control through 3D-Printed Dolphin Skin
… increase in momentum close to the wall. Time-resolved digital particle image velocimetry (TR-DPIV) is employed to document the flow behavior and quantify flow separation. The resulting backflow coefficients, boundary layer velocity profiles, Reynolds stresses, turbulent kinetic energies, …
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Near wall high resolution particle image velocimetry and data reconstruction for high speed flows
… as to develop methodology required to employ Time Resolved Digital Particle Image Velocimetry (TRDPIV) for measuring high speed, high magnification, near wall flow fields. Previous attempts to perform measurements such as this have been unsuccessful because of both limitations in equipment as …
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Vortex Dynamics and Energetics in Left Ventricular Flows
… high resolution, flow diagnostic method, Time Resolved Digital Particle Image Velocimetry (TRDPIV) in a flexible, transparent LV documenting the evolution of eddies and turbulence during a complete period of the heart cycle. The broad impact of the proposed research extends beyond the …
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Flying snakes: Aerodynamics of body cross-sectional shape
… number regime. Load cell measurements and time-resolved digital particle image velocimetry (TRDPIV) were performed on a 2D anatomically accurate model to determine the lift and drag coefficients, wake dynamics, and vortex shedding characteristics. This geometry produced a maximum lift …
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The Physical Mechanism of Heat Transfer Augmentation in Stagnating Flows Subject to Freestream Turbulence and Related Studies
… flow was studied experimentally for the first time using time-resolved digital particle image velocimetry (TRDPIV) and a new thin film heat flux sensor called the Heat Flux Array (HFA). Unique measurements of simultaneous, time-resolved velocity and surface heat flux data were obtained along …
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Passive Flow Control with Shark Skin and the Relevance of Low Speed Streaks to Denticle Actuation
… [2]. Previous experimental studies, using time-resolved digital particle image velocimetry (DPIV), have shown that the scales (samples of real shark skin) can control flow separation for flow over a hydrofoil at high angle of attack or a in a region of separation induced over a flat plate …
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Effects of Thermoacoustic Oscillations on Spray Combustion Dynamics with Implications for Lean Direct Injection Systems
… the cut-off frequency equal to the relaxation time corresponding to mean droplet size. It was also found that under acoustic forcing the droplets migrate radially away from the spray centerline and show oscillatory excursions in their movement. Non-reacting flow experiments were also performed …
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Design and Analysis of Biomimetic Medusa Robots
… to reduce the power consumption and contraction time of SMA wires, a feedback control scheme using wire resistance was developed. The controller required the knowledge of threshold resistance and safe current inputs which were determined experimentally. The overheating effect of SMA wires was …