Download or read book Integration of Cooling System with an Experimental Rig for Film Effectiveness Measurement Using a Full stage High pressure Turbine written by Jacob Ward Harral and published by . This book was released on 2005 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Increasing the efficiency in gas turbine engines requires constant improvement in the design tools currently available to the industry. One area for potential increases in efficiency deals with the film-cooling effectiveness in the high-pressure turbine section of the engine and the push to increase the temperature at the inlet of the turbine. Modeling of film-cooling effectiveness for incorporation into advanced CFD codes to be used for film effectiveness predictions and subsequent design of advanced engines is currently a major activity within the engine community. For the codes to be implemented as design tools one must gain confidence in their validity. One method that has been used for this purpose is to compare predictions obtained using these codes with experimental results obtained under as realistic conditions as is possible within the confines of controlled laboratory experiments. Under support of the NASA/DoD URETI, the OSU GTL has undertaken the task of performing detailed surface-pressure and surface heat-transfer measurements on the vane surfaces, on the blade surfaces, and on the stationary shroud of a fully cooled high-pressure turbine stage operating at design corrected conditions. Several significant changes have been made to the OSU Gas Turbine Laboratory blowdown turbine facility and to the operating mode of that facility in order to make film effectiveness measurements. One of the major facility changes was the incorporation of a coolant gas supply system (LCF) into the facility. The major changes in operating mode involved operating in blowdown mode instead of shock tube mode. In order to achieve this major change in operating procedure, it was necessary to incorporate a resistance heater into the rig just ahead of the high-pressure turbine vane inlet so that a resistance heater instead of the reflected shock could heat the test gas. The next major task was to sequence the main test gas flow with the coolant gas flow so that one could achieve the proper flow physics. This thesis will focus on the operation and integration of the LCF into the blowdown facility and on the experimental results acquired during the initial film-cooling experiment. Operation of the LCF is divided into three distinct areas: fast acting valve operation and sequencing with the main facility fast acting valve, cooling cycles, and facility controls. Successful integration of the LCF has been achieved and will be illustrated by the results of the initial film-cooling experiment. Through these experimental results and accompanying uncertainty analysis conducted as part of this thesis significant knowledge has been gained and will be applied to future film-cooling measurement programs. With the demonstrated successful operation of the OSU turbine test facility in conjunction with the LCF, the OSU GTL is capable of conducting the critical experiments necessary to provide critical verification information for ongoing film effectiveness modeling and CFD code development.

Download or read book Design of a Measurement System to Determine Cooling Effectiveness on a Rotating Turbine Rig Using Pressure Sensitive Paint written by Luis Tord Gomis and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Film cooling is widely used to protect gas turbine blades and vanes from the extremelly hot gases leaving the combustion chamber. Over the past decades, film cooling on blades, vanes and end-wall has been widely studied. In order to understand and define the process several measurement techniques have been developed. Given that numerical simulations are yet not accurate enough, as they are not able to take into account all the parameters that affect such process, the interest in experimental measurements has grown. Several measurement techniques have been used in order to calculate the film cooling effectiveness and being able to understand how the different variables affect to the overall efficiency of the process. Trying to determine film cooling efectiveness, Pressure Sensitive Paints (PSP) have been recently adapted and used. PSP have been developed since 1980s for different fluid mechanics and aerodynamic testing expermients. Since 1990s the technique is mature enough to be used and achieve high quality results in industrial wind tunnels. PSP is an absolute transducer able to convert units of surface pressure into units of light. PSP systems are able to give high precision measurements with full-surface coberture and high resolution. As PSP is a non-intrusive measurement technique, once it is designed it can be relatively easy adapted to new systems. This Master Thesis focuses on PSP technique, and aims to give a global explanation of the technique as well as a clear and precise definition of each part of the process. The main goal for this project is to design, build and test a PSP system. In order to test the PSP system, a test setup has been design, consisting in a flat test plate with cooling holes. The design of the process has been thought to be tested in the small Wind tunnel owned by the department Gasturbinen, Luft- und Raumfahrtantriebe (GLR) in the Technische Universität am Darmstadt (TUD). Although the long term objective is to adapt such system to other facilites owned by the same department such as the High Reynold Number Turbine (HiReNT) or the Large Scale Turbine Rig (LSTR).

Download or read book Prediction and Measurement of Film Cooling Effectiveness for a First stage Turbine Vane Shroud written by D. Granser and published by . This book was released on 1990 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: After compressor discharge air has initially been used to cool the heat shields of the hot gas inlet casing, it can subsequently be employed for film cooling of the first-stage vane shrouds. Since the flow field near these shrouds is three-dimensional, the film cooling effectiveness cannot be predicted correctly by common two-dimensional codes. The secondary flow transports the film from the pressure side to the suction side where it can even climb up the airfoil to cool its trailing section. Such film cooling effectiveness was first investigated experimentally in a linear vane cascade at atmospheric pressure. The temperatures and static pressure levels at the adiabatic shrouds, as well as the temperature measurements within the vane cascade, are reported for different cooling film blowing rates. In addition, the secondary flow was analysed numerically using a partially-parabolic computer code for 3D viscous flows. It involves mutual interaction of the boundary layer with the mainstream. The secondary flow can also be modelled with this algorithm, which requires less numerical effort than solving the fully 3D elliptic flow equations. The numerical results of the experiment and numerical predictions are compared. In addition, the application of these results to a high-temperature gas turbine is presented.

Download or read book Advances in Materials Sciences Energy Technology and Environmental Engineering written by Aragona Patty and published by CRC Press. This book was released on 2017-01-20 with total page 473 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 2016 International Conference on Materials Science, Energy Technology and Environmental Engineering (MSETEE 2016) took place May 28-29, 2016 in Zhuhai City, China. MSETEE 2016 brought together academics and industrial experts in the field of materials science, energy technology and environmental engineering. The primary goal of the conference was to promote research and developmental activities in these research areas and to promote scientific information interchange between researchers, developers, engineers, students, and practitioners working around the world. The conference will be held every year serving as platform for researchers to share views and experience in materials science, energy technology and environmental engineering and related areas.

Download or read book Experimental and Computational Investigation of Film Cooling on a Large Scale C3X Turbine Vane Including Conjugate Effects written by Thomas Earl Dyson and published by . This book was released on 2012 with total page 576 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study focused on the improvement of film cooling for gas turbine vanes using both computational and experimental techniques. The experimental component used a matched Biot number model to measure scaled surface temperature (overall effectiveness) distributions representative of engine conditions for two new configurations. One configuration consisted of a single row of holes on the pressure surface while the other used numerous film cooling holes over the entire vane including a showerhead. Both configurations used internal impingement cooling representative of a 1st vane. Adiabatic effectiveness was also measured. No previous studies had shown the effect of injection on the mean and fluctuating velocity profiles for the suction surface, so measurements were made at two locations immediately upstream of film cooling holes from the fully cooled cooling configuration. Different blowing conditions were evaluated. Computational tools are increasingly important in the design of advanced gas turbine engines and validation of these tools is required prior to integration into the design process. Two film cooling configurations were simulated and compared to past experimental work. Data from matched Biot number experiments was used to validate the overall effectiveness from conjugate simulations in addition to adiabatic effectiveness. A simulation of a single row of cooling holes on the suction side also gave additional insight into the interaction of film cooling jets with the thermal boundary layer. A showerhead configuration was also simulated. The final portion of this study sought to evaluate the performance of six RANS models (standard, realizable, and renormalization group k-[epsilon]; standard k-[omega]; k-[omega] SST; and Transition SST) with respect to the prediction of thermal boundary layers. The turbulent Prandtl number was varied to test a simple method for improvement of the thermal boundary layer predictions.

Download or read book Film Cooling Effectiveness on a Turbine Vane in Transonic Conditions written by Isabella Gayoso and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this experiment, measurements of the overall cooling effectiveness for a film cooled turbine vane airfoil in a high-speed cascade were obtained using infrared thermography. The vane used was the NASA C3X with impingement holes (showerhead cooling) and convective cooling holes on both the suction and pressure side. This work was done in the Mechanical Engineering Department's Experimental and Computational Convection Lab and used the high-speed cascade capability of the lab. The rationale for conducting this work was to obtain experimental data on film cooling effectiveness in a turbine vane in engine-like conditions at transonic speeds. Previous work has been done at subsonic speeds, but few pieces of literature examine this parameter at transonic speeds. The data can then be used to validate or compare to CFD models and to better understand what happens to the vane temperature distribution during engine operation. This understanding could inform the design of film cooling holes to reduce thermal strain "hot spots" which lead to failure of the vane. The results showed that trends for values of overall film effectiveness were as expected in this experiment, such as increases in blowing ratio correlating to increases in overall film effectiveness. However, the blowing ratios used in this study were not as high as values studied previously, indicating a need for more data on overall film effectiveness at transonic speeds.

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1994 with total page 652 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Heat Transfer in Gas Turbines written by Bengt Sundén and published by Witpress. This book was released on 2001 with total page 544 pages. Available in PDF, EPUB and Kindle. Book excerpt: This title presents and reflects current active research on various heat transfer topics and related phenomena in gas turbine systems. It begins with a general introduction to gas turbine heat transfer, before moving on to specific areas.

Download or read book Detailed film cooling effectiveness and three component velocity field measurements on a first stage turbine vane subject to high freestream turbulence written by Marcus Damian Polanka and published by . This book was released on 1999 with total page 718 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effect of Surface Roughness on Local Film Cooling Effectiveness and Heat Transfer Coefficients written by Douglas Neal Barlow and published by . This book was released on 1994 with total page 588 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Experimental Investigation of Air Film Cooling Applied to an Adiabatic Wall by Means of an Axially Discharging Slot written by S. Stephen Papell and published by . This book was released on 1959 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Stagnation Region Gas Film Cooling Spanwise Angled Coolant Injection written by David W. Luckey and published by . This book was released on 1976 with total page 357 pages. Available in PDF, EPUB and Kindle. Book excerpt: This experimental investigation involved the study of gas film cooling from a single row of spanwise angled holes using the stagnation region of a cylinder in cross flow to model the leading edge of a turbine vane. The objective was to obtain data for the local convective heat transfer rates to a highly cooled, curved surface exposed to a turbulent hot mainstream flow and a secondary, film coolant flow. Since the leading edge of the first stage, inlet turbine vane experiences some of the most severe thermal loads found in the turbine engine, effective film cooling is most important in this area. Film cooling of the leading edge area was modeled by making heat transfer measurements on the front stagnation region of a cylinder in cross flow. Experiments were conducted in a rectangular duct using a film cooled cylindrical test surface normal to a two-dimensional freestream flow. A gas turbine combustor provided heated air flow to simulate a Reynolds number typical of a high pressure, high temperature turbine vane. Internal convection cooling of the cylinder allowed a gas-to-wall temperature ratio of 2.1 to be achieved while using a moderate freestream gas temperature (1000R; 555K. The film coolant was chilled to obtain a coolant-to-freestream density ratio of 2.2, representative of the gas turbine environment. The cylindrical test surface was instrumented with miniature heat flux gages, and wall thermocouples to determine the influence of the film coolant blowing ratio and the injection hole geometry on the film cooling performance.

Download or read book Evaluation of Additively Manufactured Internal Cooling Channels and Film Cooling Holes for Cooling Effectiveness written by Emma Veley and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cooling of the high-pressure turbine in a gas turbine engine is essential for durability because the gas temperature entering the turbine exceeds the melting point of the hardware. Both internal and external cooling reduces the temperature of the blades and vanes. Using air that bypassed the combustor as coolant, the convective heat transfer from the hardware to this internal coolant is often augmented by ribs or a serpentine path. To cool the external surface, coolant passes through holes on the outer wall of airfoil. The coolant creates a protective film on the surface. The shape of the cooling hole influences the cooling effectiveness of this film cooling. Additive manufacturing facilitates rapid prototyping compared to traditional manufacturing methods, which can be exploited for designing and evaluating cooling schemes of gas turbine hardware. The work in this dissertation used additive manufacturing to investigate the cooling performance of several internal and external cooling schemes manufactured in at engine scale for the unique objective of determining the impacts of the internal cooling scheme on the external cooling. A variety of cooling hole shapes were investigated for this work: cylindrical hoes, meter-diffuser shaped holes, and novel optimized holes. Once additively manufactured, the as-built cooling hole surfaces were analyzed to determined their roughness and minimum cross-sectional areas. The arithmetic mean roughness of holes built at the optimal build orientation (perpendicular to the build plate) were on the order of 10 [mu]m; whereas those investigated at other build orientations had roughness values up to 75 [mu]m. For the holes built perpendicular to the substrate the minimum cross-sectional area was usually greater than the design intent but within 15%. The additive process also created an overbuilt lip on the leading edge (windward) side of the hole exit for these holes because of the thin wall thickness in the design. Using these cooling holes, the impact of rounding on meter-diffuser shaped holes and optimized holes on overall effectiveness was investigated. The rounding, which came in the form of inlet fillets on the meter-diffuser shaped holes, was found to decrease the required pressure ratio to obtain the same cooling effectiveness. The deviations from the design due to the additive process caused the novel cooling hole shapes designed through adjoint optimization to perform differently than anticipated. For example, the coolant jet from hole designed for co-flow did not bifurcate as the computational simulation showed. The cross-flow optimized hole outperformed the co-flow optimized hole for most of the tested blowing ratio when both holes were tested in a co-flow configuration. These results from the novel optimized holes proved the necessity of experimentally verifying new designs prior to incorporating into final cooling schemes. The effect of supply channel height, number of channels, ribs, and the cross-sectional shape of the supply channel was investigated to determine the impact of each on the overall effectiveness. Designs that had high overall effectiveness from only internal cooling had less augmentation in effectiveness from film cooling than designs with less effective internal cooling. For example, a ribbed channel typically had a lower film-cooling augmentation than the film-cooling augmentation for same supply channel without ribs. However, a highly effective feed channel can obtain a higher overall effectiveness without any film cooling than a poorly performing feed channel can obtain with film cooling. But the features that create a highly effective feed channel can also cause the cooling jet to lift-off the surface and mix with the hot gas path, which was seen with some rib and hole combinations and with the triangle -- vertex down supply channels. Therefore, the hole shape, the supply channel geometry, and the junction between the two all significantly contribute to a cooling scheme's performance and all three must be considered concurrently to create an optimal cooling design.

Download or read book NASA Technical Memorandum written by and published by . This book was released on 1994 with total page 492 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Film Cooling Experiments in a Medium Duration Blowdown Facility written by Issam E. Kheniser and published by . This book was released on 2010 with total page 67 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: As gas turbine engines are driven to be more efficient, quiet, and to produce less pollutant the turbine inlet temperature has a tendency to be driven upwards. The life of a turbine engine component decreases dramatically as the metal temperature increases. Because film cooling of high-pressure turbine airfoils has become common practice, improving the ability to predict film-cooling effectiveness is a critical problem of interest. Finding better, more efficient ways to use the cooling air is far preferable to using more of it. However, even if a given cooling-hole configuration proves to be effective in a flat-plate environment (which is the test article of interest in this thesis), it may not be effective on a turbine blade that is exposed to dynamic conditions that cannot be easily replicated.

Download or read book International Aerospace Abstracts written by and published by . This book was released on 1997 with total page 514 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Distribution of Film cooling Effectiveness on a Turbine Endwall Measured Using the Ammonia and Diazo Technique written by S. Friedrichs and published by . This book was released on 1995 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presented at the International Gas Turbine and Aeroengine Congress & Exposition, Houston, Texas - June 5-8, 1995.