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Showing 1 to 15 of 15 for “"boundary layer growth"”.
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Boundary layer growth in a converging nozzle
A solution to the boundary layer equations for en incompressible fluid flow through a converging nozzle is presented. Calculations are based on a nozzle whose walls have a constant radius of curvature and a 2:1 entrance area to throat area ratio. An equation for the free stream velocity es a …
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Aerodynamic drag reduction of a racing motorcycle through vortex generation
… energy freestream air with the lower energy boundary layer, delaying boundary layer growth and separation. In testing performed in the West Virginia University Closed Loop Wind Tunnel a maximum reduction of 118 drag counts (10.1%) was measured. Due to an abnormally high blockage ratio tests …
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Experimental and Numerical Study of Air Flows in a Full Scale Room
… the maximum velocity decay and the airflow boundary layer growth along both the ceiling and floor behaved like those of plane turbulent wall jets as proposed by other studies.
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An analytical study of a confined viscous vortex
… model is used to study the strong mainstream boundary layer interaction that occurs in confined vortex flows. The confined vortex flow field is divided into mainstream and boundary layer regions. A particular class of solutions of the general equations of motion is used to represent the vortex …
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Behavior of the Embedded Phase in a Shock-Driven Two-Phase Flow
… serves to identify the characteristics of the boundary layer growth behind a normal moving shock wave in a shock tunnel. Liquid propylene glycol droplets are pre-mixed with air, and slowly injected into the test section of the shock tunnel. Two test sections are evaluated during the course of …
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Supersonic wind-tunnel : nozzle design and control system analysis
… time of 30 seconds, at a Mach number of 2,35. Boundary layer growth was considered by displacing the nozzle contours outwards by the equivalent displacement thickness, while keeping the vertical tunnel side walls parallel. The five pitot probe calibration results, taken through the central …
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Incorporation of High-Fidelity Flow Field Information into Preliminary Design of Multi-Stage Axial Compressors
… as simplified models of flow features, such as boundary-layer growth, spanwise mixing, and endwall-corner separation. The methodology includes the effects of changes in radial non-uniformity and in blade geometry on the axisymmetric flow field. The approach can supersede current throughflow …
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A wind tunnel investigation of a wing-tip trailing vortex
… accelerates 6.1 % along the test section due to boundary layer growth. The potential core flow at both the entrance and exit locations is strongly uniform. The mean velocity varies .4% across the entrance and exit planes. The turbulence level at the entrance and exit locations is approximately …
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Design and flow characterization of an indraft supersonic wind tunnel for scramjet testing
… systems, ignition and flame stabilization, shock-boundary layer interaction, and aero-thermo-elastic interactions in scramjet vehicles. An indraft-type tunnel was chosen for its simplicity, low capital investment, and low power requirement. Its main features are large windows for advanced optical …
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The design and feasibility of a 10 mN chemical space propulsion thruster
… the thickness to see the effect of end wall boundary layer growth. The nozzles are tested in the MIT Space Propulsions Lab's vacuum chamber at sub atmospheric chamber pressures to match the throat Reynolds number with the micro nozzles. For the purposes of this specific design the Reynolds …
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Mean Flow Characteristics and Turbulent Structures of Turbulent Boundary Layers in Varying Pressure Gradients and Reynolds Numbers
Turbulent boundary layers flowing over a smooth surface were studied to understand the influence of varying pressure gradients and flow Reynolds number on the boundary layer growth and mean turbulent properties. The test was conducted in the Virginia Tech Stability Wind Tunnel with a 0.914 m chord …
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The Effects of Curvature on Turbulent Boundary Layers Over a 3D Bump Geometry: An Experimental Study Using BeVERLI Hill
… of the effects of curvature on turbulent boundary layers using the Benchmark Validation Experiment for RANS and LES Investigations (BEVERLI) Hill setup. The study focuses on analyzing the flow behavior over a three-dimensional bump geometry that incorporates both concave and convex …
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Characterization of performance-limiting flow mechanisms in a centrifugal compressor stage
… passage. Using a two-dimensional integral boundary layer model that is modified to accommodate three-dimensional effects as source terms, these secondary flows are shown to detrimentally impact the diffuser pressure rise capability by accumulating high loss flow along the diffuser wall near …
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The development and implementation of a hybrid rocket motor thrust stand to investigate the relationship between combustion chamber pressure and graphite rocket nozzle erosion in hybrid rocket motors
… modeling shows a non-linear increase in boundary layer thicknesses as combustion chamber pressures fall below 3.4 MPa. It is postulated that thicker boundary layer slows the diffusion of the oxidizing species to the surface thereby decreasing the rate of erosion. Thus, the modeled results …
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Thermo-hydraulic study of inclined louvered fins
… and this through the concept of the thermal boundary layer. Reducing the thermal boundary layer thickness will result in an increased heat transfer rate. In the first chapter, an overview is presented of the evolution of the fin-and-tube heat exchanger over the past decades, focused upon the …