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Showing 1 to 20 of 34 for “"Horseshoe vortex"”.
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Measurement of three-dimensional horseshoe vortex flow in a duct
… of the three-dimensional flow due to the horseshoe vortex formed at the junction of a flat wall and the leading edge of a Rankine half body. The half body is located between the parallel end walls of a duct to model the situation in turbomachinery where struts and vanes, which generate …
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Performance Improvement through Velocity Triangle Optimization-Driven Redesign for Mitigating the Horseshoe Vortex in Axial Turbines
… flow structures, such as the leading edge horseshoe vortex, resulting in significant aerodynamic performance deterioration. Reducing the effect of such flow instabilities requires turbine blade modification to discourage boundary layer roll-up, but traditional structural modification design …
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Assessment of the Thermal Improvements Awarded by Horseshoe Vortex Elimination on a Turbine Stator Blade in Computational Fluid Dynamics and Conjugate Heat Transfer
… stator blade is designed to eliminate the horseshoe vortex appearing at the leading edge. The new design is characterized by an extension of the leading edge at the hub and at the tip of about 30% of chord. By comparing this new design to an ordinary one (featuring straight leading edge), …
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Reduction of Secondary Flow Losses in a Turbine for Use in Man-Portable Power Generation
… items to be addressed is the generation of the Horseshoe Vortex. The Horseshoe Vortex is an aerodynamic phenomenon that occurs in axial turbine cascades that degrades the aerodynamic performance. This research will show that through airfoil design optimization, the Horseshoe Vortex on small …
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Effective methods of controlling a junction vortex system in an incompressible, three-dimensional, turbulent flow
… find effective methods of controlling a junction vortex system around and in the wake of a NACA 0020 body with a 1.5:1 elliptical nose mounted normal to the flat surface. Control of the junction vortex system was investigated using more slender noses and leading edge fillets. The study includes …
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Vortex flow around the bases of obstacles
… and theoretical investigations of the horseshoe vortex systems caused by boundary layer separation upstream of obstacles mounted on a wall. Flow visualization enabled these vortex systems to be described in detail for both laminar and turbulent flow upstream of the obstacles, for flow …
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Detection of secondary flow in a turbine cascade using a tracer gas technique
… an investigation into the motions of the horseshoe vortices and the passage vortex, within a plane turbine blade cascade. Fluid motion was determined using a tracer gas technique. Ethylene was injected into the pressure-side and suction-side legs of the horseshoe vortex, near the leading …
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Comparison Of Square-hole And Round-hole Film Cooling: A Computational Study
… of the exit of a film cooling hole, a so-called horseshoe vortex structure consisting of a pair of counter-rotating vortices is formed. This vortex formation has an effect on the distribution of film coolant over the surface being protected. The fluid dynamics of these vortices is dependent upon …
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A simplified vortex sheet roll-up method for formation flight
… parameter as well as a truncation of the vortex sheet in the highly rolled-up areas are introduced in order to stabilize the computations. The trailing wing is simply modeled as a lifting line, and its induced drag is computed thanks to a near-field analysis. The results are compared to …
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The Effects of Upstream Boundary Layers on the NGV Endwall Cooling
… louver cooling. The results show that the cavity vortex, the horseshoe vortex, and the passage vortex are the main factors that prevent the upstream coolant from reaching the NGV passage. The jump cooling scheme generally provides high momentum to the cooling jets. As a result, the coolant at the …
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Understanding Unsteady Corner Separation Within Wing-Body Junction Flows
… the key elements of the flow particularly the horseshoe vortex, its two bistable states, as well the location of the corner separation. These flow features were also characterized using time-averaged flow statistics. Analysis of the instantaneous flow highlighted the unsteadiness of the corner …
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Aerodynamic Investigation of Upstream Misalignment over the Nozzle Guide Vane in a Transonic Cascade
… platforms. As a main source of secondary flow, a horseshoe vortex at stagnation region of the leading edge of the vane directly influences other secondary flows. The intensity of the vortex is associated with boundary layer thickness of inlet flow. In this regard, the upstream backward-facing step …
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The Effect of Endwall Contouring On Boundary Layer Development in a Turbine Blade Passage
… of the passage due to displacement of the horseshoe vortex. However, the contour decreased heat transfer further into the passage, particularly in regions of high heat transfer, due to delayed development of the passage vortex and reduced boundary layer skew. Realistic leakage features such …
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Experimental and Numerical Study of Endwall Film Cooling
… predictions showed that the leading-edge horseshoe vortex was confined to approximately 1.5% of the airfoil span for the no film injection case and intensified with low momentum film injection. At the highest blowing ratio, the film cooling jet weakened the horseshoe vortex at the …
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Effect of Endwall Fluid Injection on Passage Vortex formation in a First Stage Nozzle Guide Vane Passage
… jet on the formation of the leading edge horseshoe vortex and the consequent formation of the passage vortex has been studied. For the computations, the Reynolds averaged Navier–Stokes (RANS) equations were solved with the commercial software ANSYS Fluent using the SST k-ω model. Total …
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Introducing, Examining and Optimising Flow Diversion Structure as an Innovative Countermeasure against Local Scour around Bridge Piers
… that the structure influenced the down-flow and horseshoe vortex and consequently reduced the scour. Based on the investigation presented herein, a flow diversion structure is a simple and easy approach for mitigation of scour at existing and new bridges.
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Parametric Investigation of the Combustor-Turbine Interface Leakage Geometry
… total pressure loss as formation of the horseshoe vortex and cross flow within the passage are affected. Scalloping phase alters local cooling levels as leakage injection is shifted laterally across the endwall.
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The effects of atmospheric turbulence on fuel consumption in extended formation flight
… between aircraft were modelled using a horseshoe vortex method, specially adapted for extended formations. The aircraft were constrained to longitudinal motion, with altitude fixed. This created a two degree of freedom formation model that is analogous to wind tunnel experimentation. A …
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The influence of blade stacking on turbine losses
… endwall boundary layer and formation of the horseshoe vortex have a strong influence on the subsequent development of the secondary flow. Numerical calculations must model this correctly in order to obtain good overall predictions.
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Assessment of a Leading Edge Fillet for Decreasing Vane Endwall Temperatures in a Gas Turbine Engine
… prevent formation of the leading edge horseshoe vortex, and preclude full development of a passage vortex. In experimental testing, four cascade inlet conditions were investigated to evaluate the effectiveness of the fillet in reducing endwall temperature levels. Two tested conditions …
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