Author: Fernando M. FerreiraPublisher:
ISBN:
Category :
Languages : en
Pages : 132
Book Description
Prediction of Turbine Blade Heat Transfer with a Turbulence Model Including Surface Curvature Effects
Author: Fernando M. FerreiraPublisher:
ISBN:
Category :
Languages : en
Pages : 132
Book Description
Prediction of Relaminarization Effects on Turbine Blade Heat Transfer
Author: Prediction of Relaminarization Effects on Turbine Blade Heat Transfer
Author: National Aeronautics and Space Administration (NASA)Publisher: Createspace Independent Publishing Platform
ISBN: 9781721286959
Category :
Languages : en
Pages : 36
Book Description
An approach to predicting turbine blade heat transfer when turbulent flow relaminarizes due to strong favorable pressure gradients is described. Relaminarization is more likely to occur on the pressure side of a rotor blade. While stators also have strong favorable pressure gradients, the pressure surface is less likely to become turbulent at low to moderate Reynolds numbers. Accounting for the effects of relaminarization for blade heat transfer can substantially reduce the predicted rotor surface heat transfer. This in turn can lead to reduced rotor cooling requirements. Two-dimensional midspan Navier-Stokes analyses were done for each of eighteen test cases using eleven different turbulence models. Results showed that including relaminarization effects generally improved the agreement with experimental data. The results of this work indicate that relatively small changes in rotor shape can be utilized to extend the likelihood of relaminarization to high Reynolds numbers. Predictions showing how rotor blade heat transfer at a high Reynolds number can be reduced through relaminarization are given. Boyle, R. J. and Giel, P. W. Glenn Research Center NASA/TM-2001-210978, NAS 1.15:210978, E-12832, Rept-2001-GT-0162
Prediction of Turbine Blade Heat Transfer by a Two-equation Turbulence Model
Author: Le Trong TranThree-dimensional Navier-Stokes Heat Transfer Predictions for Turbine Blade Rows
Author: Robert J. BoyleGas Turbine Blade Cooling
Author: Chaitanya D GhodkePublisher: SAE International
ISBN: 0768095026
Category : Technology & Engineering
Languages : en
Pages : 238
Book Description
Gas turbines play an extremely important role in fulfilling a variety of power needs and are mainly used for power generation and propulsion applications. The performance and efficiency of gas turbine engines are to a large extent dependent on turbine rotor inlet temperatures: typically, the hotter the better. In gas turbines, the combustion temperature and the fuel efficiency are limited by the heat transfer properties of the turbine blades. However, in pushing the limits of hot gas temperatures while preventing the melting of blade components in high-pressure turbines, the use of effective cooling technologies is critical. Increasing the turbine inlet temperature also increases heat transferred to the turbine blade, and it is possible that the operating temperature could reach far above permissible metal temperature. In such cases, insufficient cooling of turbine blades results in excessive thermal stress on the blades causing premature blade failure. This may bring hazards to the engine's safe operation. Gas Turbine Blade Cooling, edited by Dr. Chaitanya D. Ghodke, offers 10 handpicked SAE International's technical papers, which identify key aspects of turbine blade cooling and help readers understand how this process can improve the performance of turbine hardware.
NASA Technical Paper
Author: United States. National Aeronautics and Space AdministrationPublisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 20
Book Description
Comparison of Predicted and Measured Turbine Vane Rough Surface Heat Transfer
Author: Heat Transfer Measurements and Predictions on a Power Generation Gas Turbine Blade
Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 22
Book Description
Detailed heat transfer measurements and predictions are given for a power generation turbine rotor with 129 deg of nominal turning and an axial chord of 137 mm. Data were obtained for a set of four exit Reynolds numbers comprised of the design point of 628,000, -20%, +20%, and +40%. Three ideal exit pressure ratios were examined including the design point of 1.378, -10%, and +10%. Inlet incidence angles of 0 deg and +/-2 deg were also examined. Measurements were made in a linear cascade with highly three-dimensional blade passage flows that resulted from the high flow turning and thick inlet boundary layers. Inlet turbulence was generated with a blown square bar grid. The purpose of the work is the extension of three-dimensional predictive modeling capability for airfoil external heat transfer to engine specific conditions including blade shape, Reynolds numbers, and Mach numbers. Data were obtained by a steady-state technique using a thin-foil heater wrapped around a low thermal conductivity blade. Surface temperatures were measured using calibrated liquid crystals. The results show the effects of strong secondary vortical flows, laminar-to-turbulent transition, and also show good detail in the stagnation region.
Author: