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Showing 1 to 20 of 37 for “"Blowing ratio"”.
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Effect of Blowing Ratio on the Nusselt Number and Film Cooling Effectiveness Distributions of a Showerhead Film Cooled Blade in a Transonic Cascade
This paper investigates the effect of blowing ratio on the film cooling performance of a showerhead film cooled first stage turbine blade. The blade was instrumented with double-sided thin film heat flux gages to experimentally characterize the Nusselt number and film cooling effectiveness …
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Performance of a Showerhead and Shaped Hole Film Cooled Vane at High Freestream Turbulence and Transonic Conditions
… of 1.0/1,450,000 and 0.85/1,150,000 three blowing ratio conditions were tested: BR = 1.0, 1.5, and 2.0. At a Mach/Reynolds number of 0.60/850,000, two blowing ratio conditions were tested: BR = 1.5 and 2.0. All tests were performed at inlet turbulence intensity of 12% and length scale …
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Large Eddy Simulation of Leading Edge Film Cooling: Flow Physics, Heat Transfer, and Syngas Ash Deposition
… is injected with a 30Ë compound angle. Three blowing ratios of 0.4, 0.8, and 1.2 are studied. Free-stream Reynolds number is 100,000 and coolant-to-mainstream density ratio is unity. At blowing ratio of 0.4, the effect of coolant inlet condition is investigated. Results show that the …
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Syngas ash deposition for a three row film cooled leading edge turbine vane
… injection. The coolant to mainstream density ratio is set to unity and the freestream Reynolds number based on leading edge diameter is 32000. Coolant to mainstream blowing ratios (B.R.) of 0.5, 1.0, 1.5, and 2.0 are investigated. It is found that the stagnation cooling jets penetrate much …
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Measurements of Cooling Effectiveness Along the Tip of a Turbine Blade
… designs cool the tip. Tip gap size and blowing ratio are varied for different tip cooling configurations. Results show that the dirt purge holes provide significant film cooling on the leading edge with a small tip gap. Coolant injected from these holes impacts the shroud and floods the …
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The Effects of Upstream Boundary Layers on the NGV Endwall Cooling
… jump cooling scheme experiments investigate two blowing ratios, 2.5 and 3.5, two density ratios, 1.2 and 1.95, and three endwall profiles with different NGV-turbine alignments. Four coolant mass flow ratios from 1.0% to 4.0% are tested for the louver cooling. The results show that the cavity …
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Experimental Investigation of Particulate Deposition on a Simulated Film-Cooled Turbine Vane Pressure Surface in a High Pressure Combustion Facility
… turbine. These deposit structures may create alterations in the cooling scheme and can erode or react with thermal barrier coatings (TBC). A study was performed to examine the evolution and contributing factors to the growth of deposit structures in a simulated gas turbine environment. Tests were …
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The numerical simulation of turbulent boundary layers and film cooling
… to an example discrete hole film cooling configuration. The computational domain included the coolant supply tube as well as the main mixing region. A tube L/D of 8 and an injection angle of 35 degrees was employed for two different simulations: one was with a blowing ratio of 0.5, and the other …
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Showerhead Film Cooling Performance of a Turbine Vane at High Freestream Turbulence in a Transonic Cascade
… film cooling hole shape, coolant-to-freestream blowing ratio, coolant-to-freestream momentum ratio, surface curvature, approaching boundary layer state, Reynolds number, Mach number, combustor-generated high freestream turbulence, turbulence length scale, and secondary flows just to name a few. …
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Experimental and Numerical Study of Endwall Film Cooling
… and strong jet-mainstream interaction at higher blowing ratios, the heat transfer coefficients were amplified. A combination of film injection and unsteady passing wakes resulted in a maximum pitch-averaged and centerline heat transfer augmentation of ? 28% and 31.7% relative to the no wake and …
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Benchmarking of Computational Models Against Experimental Data for Adiabatic Film-Cooling Effectiveness for Large Spacing Compound Angle Full Coverage Film Cooling Arrays
… experimental data that tested the effects of blowing ratio, surface angle, and hole spacing for two full coverage geometries composed of cylindrical staggered holes at a compound angle of 45 degrees. These holes varied parametrically the inclination angle to be 30 and 45 degrees, while …
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Simulated Syngas Ash Deposition on the Leading Edge of a Turbine Vane with Film Cooling
… the amount of deposition while increasing the blowing ratio slightly decreased deposition. Particle deposition on the leading edge tended to cause an increase in the film cooling effectiveness. It was also found that deposition on the surface slightly increased the convective heat transfer.
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An Investigation of Effectiveness of Normal and Angled Slot Film Cooling in a Transonic Wind Tunnel
… gas ingestion into the slot was observed at low blowing ratios (M < 0.25). At high blowing ratios (M > 0.6) the cooling film was observed to "lift off" from the surface. For the 30o angled slot, the data was found to collapse using the blowing ratio as a scaling parameter (x/Ms). Results from the …
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Numerical and experimental study of flow in a gas turbine chamber.
… via simulation of the effect of varying blowing ratios (BR=1, 1.5 and 2), varying coolant fluid temperature (Tc=153 K and Tc=287.5 K), various angles of injection (35°,45° and 60°), increasing the number of cooling holes (32 and 42) and increasing the cooling holes diameter …
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Aerodynamic comparison and validation of rans, K-ω, standard K-ɛ and URANS simulations of flat plate film-cooling
… Number, Re = 7,000 based on the hole diameter at blowing ratio, BR = 0.5. The results of the RANS analyses show significant influence of the turbulent models on the predicted aerodynamics and thermal performance of the film cooling. Qualitative comparison between the simulation and experimental …
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Aerodynamics of a Transonic Turbine Vane with a 3D Contoured Endwall, Upstream Purge Flow, and a Backward-Facing Step
… and stayed closer to the endwall with a blowing ratio of 1.5 with a flat endwall (compared to no blowing with flat endwall). This was corroborated by the five hole probe results.
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Heat Transfer Coefficient and Adiabatic Effectiveness Measurements for an Internal Turbine Vane Cooling Feature
… found to be optimum for the slot design at a blowing ratio of 0.37. The pin fin arrangement along with the impingement cooling at the microcircuit entrance increased the area-averaged heat transfer by a factor of three, relative to an obstructed channel, over a Reynolds range of 5,000 to …
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A Numerical and Experimental Evaluation of the Turbulent Heat Flux in a Heated Jet in Crossflow
… to velocity, temperature, and heat flux, for a blowing ratio of 1.2, and involving a 36 K temperature difference. The relative effect on the solutions of tube and duct inflow turbulence is systematically evaluated. The impact of inherent low-pass filtering of temperature measurements and probe …
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Investigation of film cooling effectiveness from cylindrical cooling hole with anti vortex generator by numerical simulation
… respect to hole centerline. The changing of blowing ratio (BR = 0.5-1.5) was considered in this study. As for the validation, the present study was compared with the previous research done by other researchers using the results obtained from experimental data. The steady turbulence model …
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Characterization of inclined oscillating jets and crossflow interaction for use in active flow control
… with a crossflow across a range of different blowing ratios. The fluidic oscillators used in the current study featured rounded internal feedback channels and produced spatially oscillating jets at predictable frequencies. When integrated into aerodynamic bodies, fluidic oscillators have the …
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