Read Books Online and Download eBooks, EPub, PDF, Mobi, Kindle, Text Full Free.
Blade Tip Heat Transfer Measurements In A Shroudless Transonic High Pressure Turbine
Download Blade Tip Heat Transfer Measurements In A Shroudless Transonic High Pressure Turbine full books in PDF, epub, and Kindle. Read online Blade Tip Heat Transfer Measurements In A Shroudless Transonic High Pressure Turbine ebook anywhere anytime directly on your device. Fast Download speed and no annoying ads. We cannot guarantee that every ebooks is available!
Book Synopsis Blade Tip Heat Transfer Measurements in a Shroudless, Transonic, High Pressure Turbine by : Adam James Jackson
Download or read book Blade Tip Heat Transfer Measurements in a Shroudless, Transonic, High Pressure Turbine written by Adam James Jackson and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: To improve the performance of aero-engines manufacturers strive to increase the inlet temperature to the high pressure turbine. The components that are exposed to the hot gas - particularly the over-tip casing and blade tips of shroud less turbines - are vulnerable to heat damage. A previous investigation using the Oxford Rotor Facility demonstrated that a backwards facing casing step - located 20 % of high pressure blade axial chord upstream of the leading edge of the rotor - could mitigate the significant convective heat loads that the over-tip casing must withstand. This thesis describes an investigation into the effect ofthe aforementioned casing step on blade tip heat transfer rates. A second investigation, to determine the effect of the tip gap size on blade tip heat transfer rates, is also reported. These investigations necessitated the acquisition of two sets of experimental measurements. In both instances the casing step was present. The time resolved heat transfer rate data was obtained using thirty- five thin film gauges distributed over three blade tips. A small number of blade relative aerodynamic measurements were also performed. The aerodynamic measurements were valuable in helping to elucidate the mechanisms responsible for the measured changes of heat transfer rate. In order to investigate the effect of the tip gap size it was necessary to modify the over-tip casing before the second set of measurements were made. Detailed measurements of the over-tip casing were made before and after the modifications. It was shown that the mod- ifications reduced the mean tip gap to approximately two thirds ofthe baseline size. Computational fluid dynamics calculations were performed to complement the predomi- nantlyexperimental investigations. The predictive work was undertaken in order to obtain further insight into the mechanisms underpinning the changes of heat transfer rate that were observed in the experiments.
Book Synopsis Heat Transfer in the Blade Row and Tip Region of a Modern Transonic High Pressure Turbine with and Without Forward Cavity Purge Flow by : Stephen M. Molter
Download or read book Heat Transfer in the Blade Row and Tip Region of a Modern Transonic High Pressure Turbine with and Without Forward Cavity Purge Flow written by Stephen M. Molter and published by . This book was released on 2006 with total page 322 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Book Synopsis Blade Heat Transfer Measurements and Prediction in a Transonic Turbine Cascade by :
Download or read book Blade Heat Transfer Measurements and Prediction in a Transonic Turbine Cascade written by and published by . This book was released on 1999 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Endwall Heat Transfer Measurements in a Transonic Turbine Cascade by :
Download or read book Endwall Heat Transfer Measurements in a Transonic Turbine Cascade written by and published by . This book was released on 1996 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: Turbine blade endwall heat transfer measurements are given for a range of Reynolds and Mach numbers. Data were obtained for Reynolds numbers based on inlet conditions of 0.5 and 1.0 x 10(exp 6), for isentropic exit Mach numbers of 1.0 and 1.3, and for freestream turbulence intensities of 0.25% and 7.0%. Tests were conducted in a linear cascade at the NASA Lewis Transonic Turbine Blade Cascade Facility. The test article was a turbine rotor with 136 deg of turning and an axial chord of 12.7 cm. The large scale allowed for very detailed measurements of both flow field and surface phenomena. The intent of the work is to provide benchmark quality data for CFD code and model verification. The flow field in the cascade is highly three-dimensional as a result of thick boundary layers at the test section inlet. Endwall heat transfer data were obtained using a steady-state liquid crystal technique.
Book Synopsis Blade Heat Transfer Measurements and Predictions in a Transonic Turbine Cascade by :
Download or read book Blade Heat Transfer Measurements and Predictions in a Transonic Turbine Cascade written by and published by . This book was released on 1999 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Measurements of Heat Transfer, Flow, and Pressures in a Simulated Turbine Blade Internal Cooling Passage by : Louis M. Russell
Download or read book Measurements of Heat Transfer, Flow, and Pressures in a Simulated Turbine Blade Internal Cooling Passage written by Louis M. Russell and published by . This book was released on 1997 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Book Synopsis Blade heat transfer measurements and predictions in a transonic turbine cascade, ASME 99-GT-125 by : P. W. Giel
Download or read book Blade heat transfer measurements and predictions in a transonic turbine cascade, ASME 99-GT-125 written by P. W. Giel and published by . This book was released on 1999 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presented at the International Gas Turbine & Aeroengine Congress & Exhibition, Indianapolis, Indiana, June 7-10, 1999.
Book Synopsis Heat Transfer Measurements and Predictions on a Power Generation Gas Turbine Blade by :
Download or read book Heat Transfer Measurements and Predictions on a Power Generation Gas Turbine Blade written by and published by . This book was released on 2000 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Book Synopsis Blade Heat Transfer Measurements and Predictions in a Transonic Turbine Cascade by : P. W. Giel
Download or read book Blade Heat Transfer Measurements and Predictions in a Transonic Turbine Cascade written by P. W. Giel and published by . This book was released on 1999 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Measurement and Analysis of Gas Turbine Blade Tip Heat Transfer by : GM Salam Azad
Download or read book Measurement and Analysis of Gas Turbine Blade Tip Heat Transfer written by GM Salam Azad and published by . This book was released on 2000 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Local Measurement and Numerical Modeling of Mass/heat Transfer from a Turbine Blade in a Linear Cascade with Tip Clearance by : Peitong Jin
Download or read book Local Measurement and Numerical Modeling of Mass/heat Transfer from a Turbine Blade in a Linear Cascade with Tip Clearance written by Peitong Jin and published by . This book was released on 2000 with total page 600 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Studies on Transonic Turbines with Film-Cooled Blades by :
Download or read book Studies on Transonic Turbines with Film-Cooled Blades written by and published by . This book was released on 1976 with total page 109 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the third year of the contract, further advances were made towards the goal of gathering the heat transfer and aerodynamics flow data necessary for a good understanding of the performance of film-cooled, highly-loaded, transonic turbine blading. The MIT cascade blowdown facility now fully operational was used in evaluating the heat transfer performance of the four blade profiles designed in the first year of the program. The results show that the level of turbulence is an important parameter in determining heat transfer in transonic cascades. It also shows that the heat transfer to the trailing edge of the blades is very high being about 75% of the heat transfer to the leading edge. A comparison of the Nusselt number calculated from heat transfer measurements with the Nusselt number obtained by a prediction method using the pressure distribution shows good correspondence. The variation of average Stanton number over a range of Mach numbers shows that the reference blade has the most superior heat transfer performance. Preliminary data has been obtained on the off-design performance of the blades and full scale tests are underway. Comparative studies show that about 21% less heat needs to be taken out by internal cooling if one stage of a transonic turbine is used to replace two moderately loaded subsonic stages which produce the same output, have the same inlet stagnation conditions, have the same mass flow and the same tip speed. This demonstrates one of the potential advantages of transonic turbines.
Book Synopsis Aerodynamic and Heat Transfer Measurements on Blading for a High Rim-speed Transonic Turbine by : R. C. Kingcombe
Download or read book Aerodynamic and Heat Transfer Measurements on Blading for a High Rim-speed Transonic Turbine written by R. C. Kingcombe and published by . This book was released on 1989 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Turbine Blade Tip Film Cooling Measurements by : Dean Andrew Ward
Download or read book Turbine Blade Tip Film Cooling Measurements written by Dean Andrew Ward and published by . This book was released on 1992 with total page 332 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Measurement and Analysis of Gas Turbine Blade Tip Heat Transfer and Film Cooling by : Jae Su Kwak
Download or read book Measurement and Analysis of Gas Turbine Blade Tip Heat Transfer and Film Cooling written by Jae Su Kwak and published by . This book was released on 2002 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Modeling and Measurement of Heat Transfer on Turbine Blade Tips by : Hee-Koo Moon
Download or read book Modeling and Measurement of Heat Transfer on Turbine Blade Tips written by Hee-Koo Moon and published by . This book was released on 1987 with total page 424 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Measurements of Local Heat Transfer Coefficient and Film Cooling Effectiveness in Turbine Blade Tip Geometries by :
Download or read book Measurements of Local Heat Transfer Coefficient and Film Cooling Effectiveness in Turbine Blade Tip Geometries written by and published by . This book was released on 2001 with total page 57 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report results from a contract tasking Imperial College of Science. Technology and Medicine as follows: The project will involve the quantification of the flow and surface characteristics of turbine blade tip cooling geometry with velocity and turbulence distributions relevant to the gas turbine designer. The experimental program will provide measurements of the film cooling adiabatic effectiveness and heat transfer coefficient in a simulated blade tip. with injection from the pressure surface side near the tip. The program will be progressive and interactive. starting with a single row of film cooling holes with injection from the pressure surface side near the tip. moving towards other representative injection configurations: slot injection on the tip surface and groove-tip geometry. The project will supply validation data for the 3D Navier-Stokes solver Glenn-HT. currently used by NASA. and it will also provide insight into the performance of advanced cooling geometry configurations. The experiments will make use of liquid crystal thermography to obtain the heat transfer data. The data acquisition method corresponds to the steady-state technique with the use of wide band liquid crystals. It requires a reduced number of experiments when compared with narrow band crystals and thermocouples, and provides a high degree of spatial resolution and reduced uncertainty level. It will be accompanied by data from small-diameter thermocouples. hot wires and pressure transducers.
