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Showing 1 to 14 of 14 for “"Swirl Number"”.
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The Role of Swirl in the Flow Structure and Response of Premixed Flames
… a suitable method of stabilisation is required. Swirlers or bluff bodies help in stabilising the flames, by creating recirculation zones of hot combustion products, and are common in practical applications. Another issue is the coupling of acoustic waves and heat release rate oscillations which …
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Development of a Single-Point SV-LDI-1 System: A Benchmark Study for Future Experiments
… defining trends in SPL as a function of ER and swirl number (SN), and generating operability maps that describe testing conditions for future experiments with the rig. A modular redesign of the rig, including upgrades to the fuel injector, swirler, and data acquisition systems, enabled …
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3D Numerical Simulation to Determine Liner Wall Heat Transfer and Flow through a Radial Swirler of an Annular Turbine Combustor
… of a gas turbine annular combustor with radial swirlers, over a Reynolds number range from 50,000 to 840,000. A three dimensional hybrid mesh of around twenty five million cells is created for a periodic section of an annular combustor with a single radial swirler. Different turbulence models …
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Dynamics of Lean Direct Injection Combustors
… Sauter mean diameter. Next, while varying the swirl number and the venturi geometry of the combustor, the evolution of the flow field will be characterized. An in-house innovation called the Direct Rotation Swirler (DRS) is built for this purpose. The DRS uses an active geometry to provide …
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Large Eddy Simulations of high Reynolds number Complex Flows with Synthetic Inlet Turbulence
… combustors, which operate at high Reynolds numbers and high Swirl numbers. LES has several challenges which need to be surmounted for general application to complex high Reynolds number turbulent flows. The primary challenge in wall bounded flows is the need for very fine grids in the …
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The Development of a Monitoring and Control System for a Pulverised Coal-Fire Burner Using Neural Network Approach
… experiments systematically varied the burner swirl number and the secondary airflow rate over a significant range for two different coals so that both "satisfactory" and "poor" combustion conditions were obtained. The infrared emissions from the flame, the combustion noise and the acoustic …
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Flow Field and Soot Formation Characteristics in Swirl-stabilized Non-premixed Turbulent Flames
… were investigated experimentally in turbulent swirl-stabilized non-premixed flames using three different fuels: methane, ethanol and aviation Jet A-1. The studied flames were confined and stabilized in a model gas turbine combustor with a swirl number of ~0.55. Soot volume fraction, fv, and …
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Swirling jets for the mitigation of hot spots and thermal Sstratification in the VHTR lower plenum
… state-of-the-art turbulence models and advanced swirling jet technology to mitigate the two issues. The primary research goals were to increase the heat transfer and mixing capacity of swirling jets, extend swirling jet theory, and to apply those advancements for the mitigation of the …
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Investigation of Dynamics in Turbulent Swirling Flows Aided by Linear Stability Analysis
Turbulent swirling flows are important in many applications including gas turbines, furnaces and cyclone dust separators among others. Although the mean flow fields have been relatively well studied, a complete understanding of the flow field including its dynamics has not been achieved. The work …
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The Evaluation of Time-Dependent Flow in Swirl Burners
Swirl burners are widely used in industry. Recent environmental concerns, particularly on emissions from combustion processes, have introduced the requirement to modify these processes to reduce emissions whilst at the same time maintaining combustion efficiency. This thesis presents details of …
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An experimental and numerical study of surface interactions in turbulent swirling jets
… which impinge onto a surface. Traditionally, non-swirling impinging jets have been used, but interest surrounds possible advantages from imposing swirl into these jets to further promote heat and mass transfer at the surface. The challenge of resolving this question is that including swirl further …
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Numerical Analysis of Flow and Heat Transfer through a Lean Premixed Swirl Stabilized Combustor Nozzle
… several aspects of physics such as the degree of swirl imparted by the inlet fuel nozzle, premixing of the fuel and incoming air, lean premixed combustion within the combustor domain, the interaction of swirling flow with combustion driven heat release resulting in flow dilation, the resulting …
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Hydrodynamic Stability of Periodically Unsteady Axisymmetric and Swirling Jets
Axisymmetric and swirling jets are generic flows that characterize many natural and man-made flows. These include cylindrical shear layer/mixing layer flows, aircraft jets and wakes, shedding of leading edge and wing tip vortices, tornadoes, astrophysical plasma flows and flows in mechanical …
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A Computational Fluid Dynamics Investigation of Thermoacoustic Instabilities in Premixed Laminar and Turbulent Combustion Systems
… for the dynamics of laminar flat flames and swirl stabilized turbulent flames. A finite-volume based approach is being used to simulate reacting flows in both laminar and turbulent combustors. The study has been divided into three parts -- the first part involves the modeling of a …