Author: Charles Waldo HaldemanPublisher:
ISBN:
Category :
Languages : en
Pages : 380
Book Description
An Experimental Study of Radial Temperature Profile Effects on Turbine Tip Shroud Heat Transfer
Author: Charles Waldo HaldemanPublisher:
ISBN:
Category :
Languages : en
Pages : 380
Book Description
Theoretical and Experimental Study of Aerodynamics, Heat Transfer and Performance of a Radial Turbine
Author: Masters Theses in the Pure and Applied Sciences
Author: Wade H. ShaferPublisher: Springer Science & Business Media
ISBN: 1461534747
Category : Science
Languages : en
Pages : 421
Book Description
Masters Theses in the Pure and Applied Sciences was first conceived, published, and disseminated by the Center for Information and Numerical Data Analysis and Synthesis (CINDAS) * at Purdue University in 1957, starting its coverage of theses with the academic year 1955. Beginning with Volume 13, the printing and dissemination phases of the activity were transferred to University Microfilms/Xerox of Ann Arbor, Michigan, with the thought that such an arrangement would be more beneficial to the academic and general scientific and technical community. After five years of this joint undertaking we had concluded that it was in the interest of all con cerned if the printing and distribution of the volumes were handled by an interna tional publishing house to assure improved service and broader dissemination. Hence, starting with Volume 18, Masters Theses in the Pure and Applied Sciences has been disseminated on a worldwide basis by Plenum Publishing Cor poration of New York, and in the same year the coverage was broadened to include Canadian universities. All back issues can also be ordered from Plenum. We have reported in Volume 34 (thesis year 1989) a total of 13,377 theses titles from 26 Canadian and 184 United States universities. We are sure that this broader base for these titles reported will greatly enhance the value of this important annual reference work. While Volume 34 reports theses submitted in 1989, on occasion, certain univer sities do report theses submitted in previous years but not reported at the time.
Heat Transfer and Flow on the First Stage Blade Tip of a Power Generation Gas Turbine. Part 1; Experimental Results
Author: National Aeronautics and Space Administration (NASA)Publisher: Createspace Independent Publishing Platform
ISBN: 9781721184934
Category :
Languages : en
Pages : 28
Book Description
A combined computational and experimental study has been performed to investigate the detailed distribution of convective heat transfer coefficients on the first stage blade tip surface for a geometry typical of large power generation turbines(>100MW). This paper is concerned with the design and execution of the experimental portion of the study. A stationary blade cascade experiment has been run consisting of three airfoils, the center airfoil having a variable tip gap clearance. The airfoil models the aerodynamic tip section of a high pressure turbine blade with inlet Mach number of 0.30, exit Mach number of 0.75, pressure ratio of 1.45, exit Reynolds number based on axial chord of 2.57 x 10(exp 6), and total turning of about 110 degrees. A hue detection based liquid crystal method is used to obtain the detailed heat transfer coefficient distribution on the blade tip surface for flat, smooth tip surfaces with both sharp and rounded edges. The cascade inlet turbulence intensity level took on values of either 5% or 9%. The cascade also models the casing recess in the shroud surface ahead of the blade. Experimental results are shown for the pressure distribution measurements on the airfoil near the tip gap, on the blade tip surface, and on the opposite shroud surface. Tip surface heat transfer coefficient distributions are shown for sharp-edge and rounded-edge tip geometries at each of the inlet turbulence intensity levels. Bunker, Ronald S. and Bailey, Jeremy C. and Ameri, Ali A. Glenn Research Center NASA/CR-1999-209152, NAS 1.26:209152, E-11660, ASME-99-GT-169
Heat Transfer in the Blade Row and Tip Region of a Modern Transonic High Pressure Turbine with and Without Forward Cavity Purge Flow
Author: Stephen M. MolterPublisher:
ISBN:
Category : Heat
Languages : en
Pages : 322
Book Description
Abstract: A full scale rotating turbine rig operated at design corrected conditions has been used to study the heat transfer mechanisms affecting the flowpath surfaces within a modem single stage high-pressure (HP) turbine. The experimental rig was first run completely un-cooled and is currently being re-constructed to accommodate HP vane airfoil and endwall cooling and inner-stage cavity purge flow injection. Heat flux and pressure data were measured for both a flat and recessed, or squealer, HP blade tip and the stationary shroud above. The measurements indicate that the recessed tip, used in the majority of modem turbines to minimize blade damage from rubs, increases the blade heat load overall, and creates several hot spots on the floor of the recess for an un-cooled airfoil. The tip data also showed there were significant unsteady variations in the heat load at the vane passing frequency. Steady state CFD calculations were completed for both flat and squealer tip configurations to examine if the analysis could capture the details that were measured. The CFD, while not capable of estimating the unsteady heat load component and generally over predicting the overall heat flux by 10-25%, did capture the measured heat flux trends in the recessed tip. The steady state CFD prediction did show good agreement with the time-accurate data along the stationary shroud. These results show that steady-state CFD analysis can be useful in predicting the complex flow field and heat load distribution in turbine blade tips to help guide future blade designs. Pre-test CFD predictions were also performed for the upcoming series of experiments that include replacing the un-cooled vane row with a fully cooled HP vane row and the introduction of HP blade forward cavity purge flow, while leaving the HP blade un-cooled. The focus of the steady state predictions for the HP blade row was two fold; to assist in guiding the placement of new heat flux and pressure instrumentation and to study the cold flow migration through the HP blade row. Adiabatic wall temperature and Nusselt number predictions along the blade surface showed large radial, or spanwise, gradients, mostly along the suction side of the blade. Surface visualization on the suction side of the blade revealed two bands of cooler regions located at the upper and lower spans, with the middle spans being hotter, comparable to the pressure side. The lower band of cool flow is a result of the forward cavity purge flow, which mostly migrates to the suction side of the blade passage. By the trailing edge of the blade the purge flow has migrated upwards to an extent of approximately 20% of the blade span surface. The upper band of cool flow is a result of the cooling flow from the HP vane outer endwall. Blade tip secondary flows and the tip leakage vortex act to entrain this cool flow into the tip gap, resulting in its migration to the suction side of the blade. Due to a downward migration of the tip vortex along the suction side through the blade row, this cool band along the airfoil surface affects the upper 20% of the blade span. Results from the pre-test CFD predictions were also analyzed along the blade platform and rim seal surfaces. Migration of the forward cavity purge flow towards the suction side increases the Nusselt number along the rim seal and platform in these areas. Adiabatic wall temperatures on the platform surface were reasonably constant and lower than those on the blade surface, an effect of a portion of the purge flow being entrained into the platform boundary layer. Pressure asymmetries along the rim seal created circumferential variations in the local purge mass flow rates, with the leading edge of blade being the location of highest pressure and thus lower purge injection. Results also indicate the possibility of hot gas ingestion into the upper region of the rim seal at the leading edge. When data is available from the updated turbine rig, the comparisons will help to further validate this code as a useful design tool.
An Experimental Investigation of the Effects of Inlet Radial Temperature Profiles on the Aerodynamic Performance of a Transonic Turbine Stage
Author: Louis Nicholas CattafestaPublisher:
ISBN:
Category :
Languages : en
Pages : 312
Book Description
Analysis of Gas Turbine Rotor Blade Tip and Shroud Heat Transfer
Author: Ali A. AmeriPublisher:
ISBN:
Category : Gas-turbines
Languages : en
Pages : 14
Book Description
Presented at the International Gas Turbine and Aeroengine Congress &Exhibition Birmingham, UK - June 10-13, 1996.
A Reduced Model for Prediction of Thermal and Rotational Effects on Turbine Tip Clearance
Author: Measurements of Heat Transfer, Flow, and Pressures in a Simulated Turbine Blade Internal Cooling Passage
Author: Louis M. RussellPublisher:
ISBN:
Category : Flow visualization
Languages : en
Pages : 30
Book Description
An experimental study was made to obtain quantitative information on heat transfer, flow, and pressure distribution in a branched duct test section that had several significant features of an internal cooling passage of a turbine blade. The objective of this study was to generate a set of experimental data that could be used for validation of computer codes that would be used to model internal cooling. Surface heat transfer coefficients and entrance flow conditions were measured at nominal entrance Reynolds numbers of 45 000, 335 000, and 726 000. Heat transfer data were obtained by using a steady-state technique in which an Inconel heater sheet is attached to the surface and coated with liquid crystals. Visual and quantitative flow-field data from particle image velocimetry measurements for a plane at midchannel height for a Reynolds number of 45 000 were also obtained. The flow was seeded with polystyrene particles and illuminated by a laser light sheet. Pressure distribution measurements were made both on the surface with discrete holes and in the flow field with a total pressure probe. The flow-field measurements yielded flow-field velocities at selected locations. A relatively new method, pressure sensitive paint, was also used to measure surface pressure distribution. The pressure paint data obtained at Reynolds numbers of 335 000 and 726 000 compared well with the more standard method of measuring pressures by using discrete holes.
Author: