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Showing 1 to 17 of 17 for “"wing-body junction"”.
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Understanding Unsteady Corner Separation Within Wing-Body Junction Flows
<p>Wing-body junction flows, formed at the interface between a wing and fuselage surface, are a complex, coupled, three-dimensional, turbulent flow field. This thesis focused on the unsteady corner separation that develops at the trailing edge of this wing-body junction under certain conditions. A …
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The effect of a fillet on a wing/body junction flow
Time-averaged properties of a wing-body-junction flow surrounding a cylindrical wing with a 1.5:1 elliptical nose and a NACA 0020 tail have been compared to those for the above wing with a 1.5 inch radius fillet normal to the wing's surface. An attempt was made to determine the effectiveness of the …
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An experimental study of a turbulent wing-body junction and wake flow
… in an incompressible turbulent flow around a wing-body junction. The measurements were performed adjacent to the body and up to 11.56 chord lengths downstream of the body. The junction wake flow entered an adverse pressure gradient region approximately 6 chord lengths downstream. This region's …
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Skin friction measurements around a wing-body junction using oil- film laser interferometry
… to measure the skin friction around a wing-body junction in a three-dimensional, turbulent boundary layer with pressure gradients. The flow was dominated by the formation of a junction vortex generated at the nose of the wing-body. The oil-film skin friction results were compared with …
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Observation and measurements of flow structures in the stagnation region of a wing-body junction
The behavior of a junction vortex formed around an obstacle in a boundary layer flow was studied experimentally in a water tunnel for two low speed cases. A wing consisting of a 3 : 2 elliptical nose and an NACA 0020 tail was used to simulate the junction vortex. A visual study using a hydrogen …
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An experimental study of the relationship between velocity and pressure fluctuations in a wing-body junction
… tunnel in the plane of symmetry in front of a wing-body junction at an approach free-stream velocity U<sub>ref</sub>=28.3 m/s and momentum thickness Reynolds number Re<sub>θ</sub>=6900. The cylindrical wing shape was a 3:2 elliptic nose attached to a NACA 0020 tail at maximum thickness. A two …
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Measurements in the bimodal region of a wing-body junction flow with a rapidly-scanning two-velocity-component laser-Doppler velocimeter
… flow of the horseshoe vortex at the nose of a wing-body junction flow was studied. The wing consists of a 3:2 elliptic nose and a NACA 0020 tail joined at the maximum thickness (t). Measurements were performed with an approach flow conditions of U<sub>ref</sub> = 27.5 m/s, Re<sub>θ</sub> = 6700 …
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Wall Features of Wing-Body Junctions: Towards Noise Reduction
… experiments have gone into studying idealized wing-body junction flows and their impact on horseshoe vortex and wake formation. The vortices have been found to generate regions of high surface pressure fluctuations and turbulence that are detrimental to structural components and acoustics. With …
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Measurements of surface shear stresses under a three-dimensional turbulent boundary layer using oil-film laser interferometry
… driven, turbulent boundary layer around a wing body junction. Measurements were made using a dual-beam oil film laser interferometer at 56 locations. An iterative procedure was developed which increased the precision of the data extracted from the data records. Skin friction directions …
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The Impact of Three Dimensional Flow Anisotropy and Transients on Turbulence Ingestion Noise in Open Rotors
… wake ingested by a rotor mounted at the aft of a body of revolution inclined at 5 degree angle of attack. In the second configuration a transient disturbance is generated by an upstream wing body junction pitching from zero to 20 degree angle of attack . This disturbance is convected downstream …
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An experimental investigation of heat transfer in three-dimensional and separating turbulent boundary layers
… transfer was measured in the nose region of a wing-body junction formed by a wing and a flat plate. Both the wing and the endwall were heated and held at a constant uniform temperature 20 °C above ambient temperature. Heat flux rates were increased up to a factor of 3 over the heat flux rates …
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Aerodynamic Flow Control through Adapted Leading Edge Enabled by Pneumatic Artificial Muscle Actuators
… novel method for aerodynamic flow control at the wing–body junction through the use of a morphing leading-edge fairing actuated by pneumatic artificial muscles (PAMs). The compliant fairing, cast from Ecoflex® 00–31 silicone and embedded with a McKibben-type PAM actuator, was designed to …
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Design and application of a novel Laser-Doppler Velocimeter for turbulence structural measurements in turbulent boundary layers
… combines, for the first time, new techniques allowing for the direct measurement of particle acceleration and sub-measurement-volume-scale position resolution so that second-order 3D particle trajectories may be measured at high repetitions. Using these measurements, several terms in the Reynolds …
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An experimental study of a three-dimensional pressure-driven turbulent boundary layer
… turbulent boundary layer created by an idealized wing-body junction flow is experimentally studied. The body used is a 3 : 2 elliptical nosed NACA 0020 tailed symmetric profile which has a chord length of 30.5 cm (12 inches), maximum thickness of 7.17 cm (2.824 inches) , height of 22.9 cm (9.016 …
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An experimental study of coherent structures in a three-dimensional turbulent boundary layer
… flow characteristics, and there is now a large body of literature dealing with various aspects of coherent structures. However, almost all of the existing literature deal with mean two-dimensional flows with very little reported for mean three-dimensional flows. In the present study, …
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An Experimental Investigation of Pressure Fluctuations in Three-Dimensional Turbulent Boundary Layers
… turbulent boundary layer that forms away from a wing-body junction. Two of this type of boundary layer were studied - Re(theta) = 5940 and Re(theta) = 23200. The third type of flow was the separating flow about the leeside of a 6:1 prolate spheroid at angle of attack. Measurements were made at …
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Structure of 2-D and 3-D Turbulent Boundary Layers with Sparsely Distributed Roughness Elements
… boundary layers were generated by an idealized wing-body junction flow. Detailed 3-velocity-component Laser-Doppler Velocimetry (LDV) and other measurements were carried out to understand and describe the rough-wall flow structure. The measurements include mean velocities, turbulence quantities …