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Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 20 of 46 for “"Vortex Generators"”.
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Air jet vortex generators for wind turbines
Air jet vortex generators are a boundary layer control device and as such can effect a significant delay to the stall of an aerofoil. They can also reattach a separated flow, as long as the angle of attack is less than the air jets 'on' stall angle. A wind tunnel model was built and tested and then …
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A study of the application of air-jet vortex generators to intake ducts
… bend of the duct. It has been proposed that vortex generators may be usefully employed in such intake ducts to enhance the homogeneity of the pressure distribution at the engine face, and hence, reduce the unsteady loading on the engine. Both vane and air jets have been tested experimentally …
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The effects of micro-vortex generators on normal shock wave/boundary layer interactions
… work concentrates on analyzing the effects of vortex generators (VGs) as a flow control method by contributing a greater understanding of the flowfield generated by these devices and characterizing their effects on the SWBLI. The vortex generators are utilized with the goal of improving …
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Large eddy simulation of shock boundary layer interaction control using micro-vortex generators
… a novel type of flow control device called micro-vortex generators (µVGs) which may offer similar control benefits without the bleed penalties. µVGs have the ability to alter the near-wall structure of compressible turbulent boundary layers to provide increased mixing of high speed fluid which …
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Air-Side Heat Transfer Enhancement for Offset -Strip Fin Arrays Using Delta Wing Vortex Generators
The re-generated streamwise vortices in the middle of the array are found to be weaker and decay more quickly in the flow direction than the streamwise vortices generated at the inlet of the array.
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Aerodynamics and multi-fidelity surrogate modelling of an inverted wing with vortex generators in ground effect
A study of an inverted single-element wing with vortex denerators in ground effect is presented. Counter-rotating and co-rotating rectangular-vane type vortex generators with different device heights are studied on the suction surface of the wing. The primary application of this study is a front …
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An experimental investigation of the use of air jet vortex generators to control shock induced boundary layer separation
Air jet vortex generators were originally investigated by R.A. Wallis. Results showed that their effectiveness in delaying shock induced boundary layer separation was not as good as conventional vane type generators. Recent low speed wind tunnel tests carried out at City University indicated that …
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Effects of Louver Length and Vortex Generators to Augment Tube Wall Heat Transfer in Louvered Fin Heat Exchangers
There are several different types of compact heat exchangers used in applications where small size and weight are required. One particular type of compact heat exchanger, the louvered fin heat exchanger, has been used heavily in the automotive and air conditioning industries. Over the last several …
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The effects of vortex generating fins and jets on the crossflow separation of a submarine in a turning maneuver
The effect of fin and jet vortex generators on the crossflow separation of a 688 class submarine in a turning maneuver was studied. The vortex generators are located on the top and bottom centerline of the submarine. The intent of the vortex generators is to improve turning performance by changing …
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The development of passive flow control vortices
… the flow-field of sub-boundary layer vane vortex generators (VVGs) and steady jet vortex generators (SJVGs) in a separated flow at 20m/s. The vortex generators were mounted on a 2D bump which was situated on the floor of a 350mm by 250mm wind tunnel and had a separation zone on its trailing …
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Near Wall Investigation of Three Dimensional Turbulent Boundary Layers
… a vortical flow created by two half-delta wing vortex generators. Near wall secondary flow features are found. The second flow is an investigation of the first quarter chord tip gap flow in the cascade tunnel. Strong three-dimensional phenomena are found. The third flow investigated is the …
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Design and development of a rectangular supersonic wind tunnel facility for the study of shock/boundary layer interactions
… layer interaction control options, called micro-vortex generators. A new supersonic wind tunnel was designed and built on the University of Illinois campus to enhance high-speed flow testing capabilities used for studying these flow-control devices. A newer and larger tunnel will also contribute …
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Shipping decarbonization through sea route optimization & Vortex generator resistance reduction
… this thesis also discusses and tests the use of Vortex generators (VGs) as an innovative tool for ship resistance reduction. The theory shows that the use of VGs is an effective method for potentially reducing ship’s form factor resistance, with an expected reduction of up to 30% of total …
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An Experimental Study of Longitudinally Embedded Vortices in a Turbulent Boundary Layer via the Non-Invasive Comprehensive LDV Technique
… of boundary layers have been proposed, but vortex generators have proven to be an economical choice as they are often used to fix deficiencies in a flow field after large scale production of a vehicle has commenced. In order to better understand the interaction between vortex generators and …
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Development of UAV flight test demonstrator for cyclotronic arc-plasma actuator
… These actuators can be used in a role similar to vortex generators, though with the additional ability of being enabled or disabled for flight regimes such as takeoff and landing. As disabling these actuators during cruise can reduce or eliminate drag penalties, these devices could be used as …
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Correlation between Unsteady Loading and Tip Gap Flow Occurring in a Linear Cascade with Simulated Stator-Rotor Interaction
… of inlet guide vanes and the compressor casing, vortex generators were glued to a moving end wall. In this investigation, the tip clearance was varied from 0.83% to 12.9% chord. Measurements of the midspan and the tip blade loading were made using static pressure taps. The tip loading shows that …
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Predicting the Interaction Between Energy Saving Devices on Surface Ships
… Two novel energy saving devices were explored: vortex generators and a morphing bow foil. A deep dive into how each of these devices work to reduce drag was completed and experiments were carried out in the Parson’s Laboratory Towing Tank. The vortex generator designs were iterated many times to …
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Development and analysis of techniques to improve air-cooling and temperature uniformity in battery packs
… by incorporating inlet plenum, jet inlets, and vortex generators. The proposed battery pack concept reduced the maximum temperature by about 6%. Furthermore, the temperature difference between the maximum temperature and the minimum temperature exhibited by the battery pack was reduced by 24%. …
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Exploring Complex Problems in Fluid Dynamics: from CFD to Experiments Leveraging ML
… to theory and applications: 1. Optimizing Vortex Generators to Reduce Ship Form Drag: In the quest for reducing ship emissions, it is imperative that the fluid mechanics of ship resistance be explored for improving propulsive efficiency. Form drag is a significant part of the resistance of …
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