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Showing 1 to 15 of 15 for “"Purge Flow"”.
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Influence of Purge Flow Swirl and Passage Discrete Hole Injection Angle on Turbine Blade Endwall Cooling
… challenge due to the complex secondary flow structures within blade passages. Purge flow coolant, which passes through the gap between the stator and rotor, and discrete cooling holes, which are positioned strategically within the coolant passage, are often utilized together to provide …
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Experimental Study of the Heat Transfer on a Squealer Tip Transonic Turbine Blade with Purge Flow
The objective of this work is to examine the flow structure and heat transfer distribution of a squealer tip rotor blade with purge flow cooling and provide a comparison with a basic flat tip rotor blade without purge flow cooling, under transonic conditions and high inlet free stream turbulence …
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Aerodynamics of a Transonic Turbine Vane with a 3D Contoured Endwall, Upstream Purge Flow, and a Backward-Facing Step
… a non-axisymmetric endwall contour and upstream purge flow on the secondary flow of an inlet guide vane. Three cases were tested in a transonic wind tunnel with an exit Mach number of 0.93-a flat endwall with no upstream purge flow, the same flat endwall with upstream purge flow, and a 3D …
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Impact of unsteady secondary air flow interaction with main flow on loss generation in axial turbines
Secondary air, often called purge air, is injected through the endwall gap between stationary vanes and rotating rotors in axial turbines to prevent ingestion of the hot working gas into the endwall cavities. Three-dimensional flow computations, unsteady as well as steady, have been carried out to …
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Experimental and analytical assessment of cavity modes in a gas turbine wheelspace
… turbine engine operating conditions with purge flow. The experimental results and observations are complemented by computational assessments of cavity modes associated with flow in canonical cavity configurations. The cavity modes identified include Shallow Cavity modes and Helmholtz …
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Assessment of Scaling Rule for Hot Gas Ingestion in Representative Turbine Rim Seal System for Large Industrial Gas Turbines
… sealing parameter consists of the ratio of purge mass flow rate to a characteristic mass flow rate based on the rim seal geometry and rim speed, rotational Reynolds number, purge flow Reynolds number, rim-seal Reynolds number, and Rossby number. The geometry and operating conditions of the …
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Secondary air interaction with main flow in axial turbines
Secondary air, known as purge air, is injected through seals in the hub and shroud of axial turbines to prevent hot gas ingestion into the endwall cavities. An investigation into the interaction of purge ow with turbine main ow has been undertaken, to determine where losses are generated, how they …
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Mechanisms of hot gas ingestion in turbine disk cavities
… ingestion occurs when gas from the mainstream flow path migrates into the cavities between stator and rotor disks. In order to mitigate the damage caused by these high-temperature gases, the cavities are purged with colder air from the compressor, and rim seals are used at the entrance from the …
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DEVELOPMENT AND TESTING OF A NEW AIR-ASSISTED FLARE SYSTEM FOR LOW FLOW CONDITIONS
… combustion efficiency falls below 96.5%. Low flowrates of waste gases (purge flow conditions) results in flares with combustion efficiency less than 96.5%. During normal operating conditions, these flares process much lower flows of flare gas than they are optimally designed to process. This …
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Heat Transfer and Flow Characteristics on the Rotor Tip and Endwall Platform Regions in a Transonic Turbine Cascade
… endwall regions. The heat transfer and secondary flow characteristics were analyzed for different engine relevant configurations and exit Mach/Reynolds number conditions. The experiments were conducted in a linear blowdown cascade at transonic high turbulence conditions of Mexit ~ 0.85, 0.60 and …
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Computational assessment of turbine rim seal system parametric variation on hot gas ingestion and flow pattern
… parametric variation on hot gas ingestion, flow pattern, and turbine stage efficiency. The parameters focused on are purge to main mass flow rate ratio, axial gap to rim radius ratio, radial gap to rim radius ratio, normalized axial position of the blade leading edge, and internal purge …
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Characterization of turbine rim seal flow and its sealing effectiveness
… turbine engine, ingestion of hot gas from the flowpath into the gaps between the turbine rotor and stator can lead to elevated metal temperatures and a deterioration of component life. To prevent ingestion, bleed air from the compressor is used to "purge" the rim seal cavities. Establishing a …
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Experimental Study of Gas Turbine Endwall Cooling with Endwall Contouring under Transonic Conditions
… platform through efficient control of secondary flow vortices. Complex vortices form due to the interaction between the incoming boundary layer and endwall-airfoil junction at the leading edge which entrain the hot gases towards the endwall, thus increasing surface heat transfer along its …
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The Effect of Density Ratio on Steep Injection Angle Purge Jet Cooling for a Converging Nozzle Guide Vane Endwall at Transonic Conditions
… rates for a typical nozzle guide vane platform purge jet cooling scheme. An axisymmetric converging endwall with an upstream doublet staggered cylindrical hole purge jet cooling scheme was employed. Nominal exit flow conditions were engine representative and as follows: {rm Ma}_{Exit} = 0.85, …