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Showing 1 to 20 of 151 for “"Flowfield"”.
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Flowfield measurements in a transonic turbine
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1995.
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Computational Assessment of Axial Compressor Flowfield Instability
At low flow rates, the flowfield of axial compressors becomes unstable. Two examples of this are rotating stall (a compression system level instability) and so-called “Rotating Instabilities” (a localized fluctuation in the tip flow region). This thesis presents full-annulus URANS computations …
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Flowfield study of a close-coupled canard configuration
… five-hole pressure probe was used to complete a flowfield survey behind a close-coupled canard and wing model set a 32 degrees angle of attack. The canard and wing were both low-aspect-ratio, highly swept, delta platforms with rounded leading edges. The model was set at to condition of maximum …
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Aerodynamics study of the flowfield at a shelterbelt
… than total wind-speed reduction in the whole flowfield. The purpose of this study is to formulate a Navier-Stokes based scheme to simulate the turbulent aerodynamic characteristics of a shelterbelt. Qualitative results from field observation of a living-tree shelterbelt under real atmospheric …
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Ice-Induced Unsteady Flowfield Effects on Airfoil Performance
Vortex structures observed in the shear layer were presumed to be the cause of large-scale pressure fluctuations upstream of reattachment at small angles of attack. Pressure spectra near reattachment exhibited wide bandwidth frequency peaks that indicated a non-periodic phenomenon and corresponded …
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Information based sensor control in a two-vortex flowfield
… optimally controlled sensor platform in a vortex flowfield. The question raised is: ""How to control a UAV network evolving in a set of two vortices to collect the best data from these vortices?"". The control part is based on information theory where the cost function is built using the the …
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Flowfield Downstream of a Compressor Cascade with Tip Leakage
… cascade with tip leakage was built. The flowfield downstream of the cascade was measured using four sensor hot-wire anemometers, from which the mean velocity field , the turbulence stress field and velocity spectra were obtained. Oil flow visualizations were done on the endwall underneath …
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Turbulent flowfield downstream of a perpendicular airfoil--vortex interaction
… were performed to document the turbulent flowfield produced downstream of an airfoil encountering an intense streamwise vortex. This type of perpendicular airfoil--vortex interaction commonly occurs in helicopter rotor flows. The experiments presented here thus provide useful information …
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The characterization of the flowfield of a dump combustor
… effects of combustion on a typical ramjet engine flowfield, a water-cooled, stainless steel dump combustor model was developed. A two-component Laser Doppler Anemometer (LOA) was used to measure the mean and turbulent velocities in the axial and tangential directions and provide a comparison …
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A Rigorous Solution for Finite-State Inflow throughout the Flowfield
<p>In this research, the Hseih/Duffy model is extended to all three velocity components of inflow across the rotor disk in a mathematically rigorous way so that it can be used to calculate the inflow below the rotor disk plane. This establishes a complete dynamic inflow model for the entire flow …
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Local flowfield about large distributed roughness elements in a laminar boundary layer
The local flowfield about large roughness elements placed in a flat plate laminar boundary layer was studied. Flowfield measurements were taken upstream, over, and downstream of an isolated hemispherical roughness element and distributed hemispherical roughness elements. The height of the roughness …
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Arbitrary Lagrangian-Eulerian form of flowfield dependent variation (ALE-ADV) method for moving boundary problems
Flowfield Dependent Variation (FDV) method is a mixed explicit-implicit numerical scheme that was originally developed to solve complex flow problems through the use of so-called implicitness parameters. These parameters determine the implicitness of FDV method by evaluating local gradients of …
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Conditionally Analyzed Mean Velocity and Turbulence Measurements in a Plume-Induced Boundary Layer Separated Flowfield
The shock-induced separation process was found to dramatically increase the streamwise and transverse Reynolds normal stresses (which both peak near reattachment), the primary shear stress, and the normal stress anisotropy. The shock-separated shear layer consists of only a single layer with a …
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Unsteady modes in the flowfield about an airfoil with a leading-edge horn-ice shape
An analysis of unsteady modes present in the flowfield of an airfoil with a leading-edge horn-ice shape was performed in the current study. An NACA 0012 airfoil was tested in a subsonic wind tunnel at Re = 1.8 × 106. In addition to the clean configuration, the airfoil model was also tested with a …
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An experimental investigation of unsteady separation shock wave motion in a plume-induced, separated flowfield
… plume-induced, boundary layer separated (PIBLS) flowfields has been conducted. The PIBLS flowfields were created in a blowdown-type wind tunnel designed specifically to produce PIBLS in a planar, two-stream, supersonic flow. In this unique wind tunnel, separation of the freestream boundary layer …
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Flowfield measurements in the vortex wake of a missile at high angle of attack in turbulence
The flowfield downstream of a vertically-launched surface-to-air missile model at an angle of attack of 50° and a Reynolds number of 1.1 x 10(5) was investigated in a wind tunnel of the Naval Postgraduate School. The goal of this thesis is to experimentally validate the pressure measurement system …
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An experimental investigation of the two-stream, supersonic, near wake flowfield behind a finite-thickness base
… high-speed flight and characterizes the aft-end flowfield of powered missiles in supersonic flight. In order to examine fundamental mechanisms and interactions ongoing in this near-wake region, an experimental investigation was conducted to obtain mean and turbulence data in a wind tunnel. The …
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An Experimental Study of the Flowfield on a Semispan Rectangular Wing With a Simulated Glaze Ice Accretion
… effect of a simulated glaze ice accretion on the flowfield of a semispan, reflection-plane, rectangular wing at Re = 1.5 million and M = 0.12 was investigated. A laser Doppler velocimeter was used to map the flowfield on the upper surface of the model in both the clean and iced configurations at …
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Numerical Studies of the Jet Interaction Flowfield with a Main Jet and an Array of Smaller Jets
… contribution comes from the jet interaction flowfield, the interaction of the expanding injectant with the crossflow. This interaction produces areas of high pressure ahead of the injector and areas of low pressure in the region aft of the jet. The combination of the high-pressure regions in …
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