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Showing 1 to 20 of 46 for “"water tunnel"”.
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Measurements of Wings at Very Low Reynolds Numbers
… performance at very low Reynolds numbers in a water tunnel. The lift and drag behavior for rectangular wings with discretely angled wing profiles and aspect ratio were obtained at Reynolds numbers between 4,000 and 10,000. This thesis is intended to inform both future force measurement …
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An Investigation of the Hydrodynamic Effects of Enteromorpha clathrata Fouling on Hydrofoils
… chord and 8 inch span were used in this study. A water tunnel facility was designed and constructed to perform the tests, and the results were verified using computational fluid dynamic modeling. The CFD software package <em>Fluent </em>was used to create a two dimensional model of the water …
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Experimental analysis of an energy self sufficient ocean buoy utilizing a bi-directional turbine
… impulse bi-directional turbine which used sea water as the working fluid. Testing was conducted in a recirculating water tunnel, and two flow visualization techniques were applied. This was the first project in the MIT water tunnel since a major renovation and upgrade., and thus included a …
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Unsteady pressure and vorticity fields in blade-vortex interactions
… Velocimetry system is used to take data in a water tunnel. Ensemble-averaged velocity fields are obtained in the region of the leading edge of the airfoil. Finite-difference algorithms were written to obtain vorticity and pressure in the data field. Computer animation of the unsteady vorticity …
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Implementation of 3DPTV for turbulence analysis and subgrid-scale stress model testing of a backward-facing step flow
… to a backward-facing step flow in a small-scale water tunnel testing facility. The camera system, consisting of three 4008 $\times$ 2672 CCDs, was aligned and calibrated using a custom grid and dot target plate mounted on a purpose-built rig, containing a precision single-axis translation stage. …
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The Testing and Verification of a Nanomembrane Based Pressure Sensor for Small-Scale Underwater Pressure Measurements
… and quantifying small-scale disturbances in underwater environments. A highly sensitive MEMS pressure sensor has been developed that can be packaged in two different ways – one in a cylindrical housing, and the other in a flexible, yet robust, strip configuration – enabling more freedom for the …
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The Development and Control of Axial Vortices over Swept Wings
… the Engineering Science and Mechanics (ESM) Wind Tunnel at a Reynolds number Re = 210,000. Data were taken in five crossflow planes surrounding the wing's trailing edge. Results showed a dominant narrowband Strouhal frequency of St = 1.5 covering approximately 80% of the area with lower-intensity …
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Separation and wakes over three-dimensional bodies
… Velocimetry. Experiments were conducted in a water tunnel and the flow was visualized with dyes. The measurement of three-dimensional boundary layers required a special design of the laser optics. Attention was focused in the neighborhood of three-dimensional separation. The Vortex-Lattice …
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Airfoil response to periodic disturbances: the unsteady Kutta condition
… are considered. Measurements were obtained in a water tunnel by Laser-Doppler velocimetry. Ensemble-averaged velocity measurements were obtained in the vicinity of the trailing edges of both the pitching and the fixed airfoils. The flowfields in the wake and at the trailing edges of both airfoils …
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FEASIBILITY OF USING EXPERIMENTAL LOAD MEASUREMENTS ON A CYLINDER TO PERFORM PHASE-SENSITIVITY ANALYSIS IN THREE-DIMENSIONAL FLOWS
… data was collected using a recirculating water tunnel, custom translating test fixture, and load cell at the Naval Postgraduate School. Analysis of this data utilizes custom written MATLAB scripts to discern phase offset jumps from multiple trials for two different test conditions. Phase …
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Reduction of unsteady underwater propeller forces via active tail articulation
… and testing was completed in a closed-channel water tunnel at the Naval Undersea Warfare Center in Newport, RI. A propeller-force measurement apparatus was designed and built to measure the forces and moments created by a spinning propeller behind a life scale stator model. Tests were conducted …
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Design, build and test of an axial flow hydrokinetic turbine with fatigue analysis
… was tested. Tests were conducted in the MIT water tunnel for tip speed ratios ranging from 1.55 to 7.73. Additional code was also written and added to OpenProp in order to implement ABS steel vessels rules for propellers and calculate blade stress. The blade stress code was used to conduct a …
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Flow study of the nozzle region of the space shuttle solid rocket motor
… SRM test firings. The SRM was simulated by water flow through a plexiglas model mounted in a water tunnel. Dye and hydrogen bubble visualization techniques along with hot water analysis methods were used to detect flow patterns. Visual results recorded on video tape indicated strong …
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Experimental and finite-element investigation of flow past single and multiple cylinders
… velocimetry and flow visualization obtained in a water tunnel and skin friction, pressure, lift, drag and hot-wire measurements obtained in a wind tunnel. Both steady and pulsed flows are considered. Numerical work consists of finite element analysis of Navier-Stokes and energy equations governing …
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Internal flow investigation of an aft finocyl grain configuration in a solid rocket motor
… tests were conducted in mediums of air and water to investigate the internal flow field about the nozzle region of a proposed solid rocket motor (SRM) configuration that would potentially replace the current external boosters on NASA's Space Shuttle. One-eighth-scale clear acrylic models of …
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The Effect of Persistent Vortices on Boundary Layer Behavior in Turbulent Flow along a Kelvin-Stuart Cat's Eyes Wavy Wall
… flow visualization and hot-wire experiments in a water tunnel at moderate Reynolds number reveal that a persistent vortex will relaminarize the boundary layer along wavy even in the presence of freestream turbulence. This result is consistent with Dawson [7] who found similar boundary layer …
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An investigation of eddy diffusivities of momentum and heat in circular pipes.
… of momentum and heat were obtained in a water tunnel Results were obtained for Reynolds numbers from 2 x 10 5 to 9 x 10 5. Pipes were roughened internally with paint mixed with fine particles and roughness ratio r/k ranging between 7.2 x 10 3 and 2.5 x l0 5 with absolute roughness height …
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A New Multifunctional MEMS-Based Piezoresistive Pressure Sensor for Monitoring Static, Acoustic, and Turbulent Events in Underwater Applications
… sensors were evaluated though extensive water tunnel testing. Two sensors were surface mounted into a NACA 0018 hydrofoil and evaluated under a range of angles of attack (AoAs) and flow speeds. The results highlight the sensors' proficiency in monitoring static flow perturbations, …
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Experimental Investigations into Shark Skin Inspired Active Flow Control Mechanisms
… frequencies from 0.48 Hz to 5.13 Hz within a water tunnel in a separating turbulent boundary layer flow. These tests were then compared to a corresponding smoothplate case. In the first set of tests, a zero pressure gradient case, it was found that the actuation of the flaps increased the …
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