Download or read book An analytical prediction of the effects of film cooling on gas turbine blades written by Kevin Lloyd Miller and published by . This book was released on 1984 with total page 278 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Survey of Advantages and Problems Associated with Transpiration Cooling and Film Cooling of Gas turbine Blades written by Ernst Rudolf Georg Eckert and published by . This book was released on 1951 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: Summary: Transpiration and film cooling promise to be effective methods of cooling gas-turbine blades; consequently, analytical and experimental investigations are being conducted to obtain a better understanding of these processes. This report serves as an introduction to these cooling methods, explains the physical processes, and surveys the information available for predicting blade temperatures and heat-transfer rates. In addition, the difficulties encountered in obtaining a uniform blade temperature are discussed, and the possibilities of correcting these difficulties are indicated. Air is the only coolant considered in the application of these cooling methods.

Download or read book Effects of Film Cooling on Turbine Blade Tip Flow Structures and Thermal Loading written by Louis Edward Christensen and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gas turbine engines are an essential technology in aviation and power generation. One of the challenges associated with increasing the efficiency of gas turbines is the thermal loading experienced by the engine components downstream of the combustors especially the high-pressure turbine blades. High temperatures and rotational velocities can cause blade failures in numerous ways such as creep or stress rupture. Technologies like film cooling are implemented in these components to lower the thermal loading and reduce the risk of failure. However, these introduce complexities into the flow which in turn increases the difficulty of predicting the performance of film cooled turbines. Accurately predicting the capabilities of these components is essential to prevent failure in gas turbine engines. Engineers use a combination of experiments and computational simulations to understand how these technologies perform and predict the operating conditions and lifespan of these components. A combined experimental and numerical program is performed on a single stage high-pressure turbine to increase understanding of film cooling in gas turbines and improve computational methods used to predict their performance. The turbine studied is a contemporary production model from Honeywell Aerospace with both cooled and uncooled turbine blades. The experimental work is performed at The Ohio State University Gas Turbine Laboratory Turbine Test Facility, a short duration facility operating at engine corrected conditions. The experiments capture heat flux, temperature, and pressure data across the entire blade, but this work will focus on the turbine blade tip data. Tip temperature data are captured using a high-speed infrared camera providing a unique data set unseen in the current literature. In addition to the experiments, transient conjugate heat transfer simulations of a single turbine passage are performed to recreate the experiments and give insight into the flow field in the tip region of the turbine blades. The experiments and simulations are conducted to provide a better understanding of the interactions of the film cooling and tip flows along with their relationship to the thermal loading on the turbine blade tip. Film cooling in the tip region adds complexity to the flow and a non-intuitive relationship exists between film cooling and thermal loading. Addition of cooling is not guaranteed to reduce the thermal loading on the blade tips. Cooling jets can displace hot gases protecting the blade, but they are also capable of shifting flow structures and trapping hot gases near the blade surface especially so in corners of the blade tips. These direct and indirect methods of altering the thermal loading open a new path to optimization where engineers consider how the coolant alters the flow in addition to forming a protective layer of cool gas. This can be done to more effectively use coolant not only in the blade tips but elsewhere on the turbine blades leading to higher engine efficiencies and more sustainable gas turbine engines.

Download or read book Prediction of Film Cooling on Gas Turbine Airfoils written by and published by . This book was released on 1994 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Analysis of Combined Convective and Film Cooling on an Existing Turbine Blade written by and published by . This book was released on 2003 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt: To support gas turbine operators NLR is developing capabilities for life assessment of hot engine components. As a typical example the first rotor blades of the high pressure (HP) turbine of the F-lOO-PW-220 military turbofan will be discussed. For these blades tools have been developed to derive the blade temperature history from flight data obtained from F-16 missions. The resulting relative life consumption estimate should support the Royal Netherlands Air Force in their engine maintenance activities. The present paper describes the prediction method for the blade temperature based on reverse engineering. Input data are the flight data of the engine performance parameters and the geometry of the HP turbine blades and vanes including film cooling orifices. The engine performance parameters are converted in HP turbine entry and exit conditions by the NLR Gas Turbine Simulation Program (GSP) engine model. Next a Computational Fluid dynamics (CFD) tool is used to calculate the resulting flow field and heat transfer coefficients without film cooling. An engineering method is used to predict the internal cooling and the resulting film injection temperature. The film cooling efficiency is estimated and a finite element method (FEM) for heat conduction completes the analysis tool. The method is illustrated by results obtained for the engine design point.

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 Gas Turbine Blade Cooling written by Chaitanya D Ghodke and published by SAE International. This book was released on 2018-12-10 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Download or read book Effect of Film Hole Shape on Turbine Blade Film Cooling Performance written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-05-30 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt: The detailed heat transfer coefficient and film cooling effectiveness distributions as well as tile detailed coolant jet temperature profiles on the suction side of a gas turbine blade A,ere measured using a transient liquid crystal image method and a traversing cold wire and a traversing thermocouple probe, respectively. The blade has only one row of film holes near the gill hole portion on the suction side of the blade. The hole geometries studied include standard cylindrical holes and holes with diffuser shaped exit portion (i.e. fanshaped holes and laidback fanshaped holes). Tests were performed on a five-blade linear cascade in a low-speed wind tunnel. The mainstream Reynolds number based on cascade exit velocity was 5.3 x 10(exp 5). Upstream unsteady wakes were simulated using a spoke-wheel type wake generator. The wake Strouhal number was kept at 0 or 0.1. Coolant blowing ratio was varied from 0.4 to 1.2. Results show that both expanded holes have significantly improved thermal protection over the surface downstream of the ejection location, particularly at high blowing ratios. However, the expanded hole injections induce earlier boundary layer transition to turbulence and enhance heat transfer coefficients at the latter part of the blade suction surface. In general, the unsteady wake tends to reduce film cooling effectiveness.Han, J. C. and Teng, S.Glenn Research CenterHEAT TRANSFER COEFFICIENTS; COOLANTS; TEMPERATURE PROFILES; SUCTION; TURBINE BLADES; HEAT MEASUREMENT; FILM COOLING; BOUNDARY LAYER TRANSITION; CASCADE WIND TUNNELS; CYLINDRICAL BODIES; EJECTION; GAS TURBINES; HOLE DISTRIBUTION (MECHANICS); LIQUID CRYSTALS; LOW SPEED; THERMAL PROTECTION; THERMOCOUPLES; WIND TUNNELS

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 702 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Numerical Study of the Effect of Wake Passing on Turbine Blade Film Cooling written by James D. Heidmann and published by . This book was released on 1995 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effect of Film Hole Shape on Turbine Blade Film Cooling Performance written by and published by . This book was released on 2000 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Gas Turbine Blade Cooling written by Chaitanya D Ghodke and published by SAE International. This book was released on 2018-12-10 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Download or read book Aerodynamic Loss Models and Multi dimensional Prediction of Discrete Hole Film Cooling on Gas Turbine Blades written by İlker Topçuoğlu and published by . This book was released on 2013 with total page 145 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Curvature Effects on the Heat Transfer Performance of Three Dimensional Film Cooling of Gas Turbine Blades written by E. R. G. Eckert and published by . This book was released on 1982 with total page 65 pages. Available in PDF, EPUB and Kindle. Book excerpt: Film cooling is used extensively for the blades of high-performance, high-temperature gas turbines, especially for aircraft turbines. In this method, a film of coolant is injected into the boundary layer covering the skin of the blades and creating a cool layer which separates the blade surface from the hot gas stream and, in this way, reduces the blade temperature. For best performance the coolant should be injected through a slot or a strip of porous material. This, however, is not possible for turbine blades because of strength considerations, and the coolant is injected through one or several rows of holes. For aircraft gas turbines, air is used as a coolant. The present investigation, therefore, is concerned with the cooling performance of film cooling when cooling air is injected into the boundary through one or two rows of holes. A standard configuration of the coolant holes is used because it has been used in previous investigations and because configurations in actual turbine blades are close to it. The cooling holes are arranged at a distance apart equal to three times the hole diameter. For injection through two rows of holes, the two rows are staggered and the centers of the holes are on the corners of equilateral triangles. The channels which end at the blade skin in the cooling holes are inclined by an angle of 35 deg against the skin surface in the downstream direction.

Download or read book Turbine Engine Hot Section Technology 1987 written by and published by . This book was released on 1987 with total page 492 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Stress Analysis of Gas Turbine Blade with Film Cooling written by Diwakar Awate and published by . This book was released on 2017 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Numerical Analysis of Heat Transfer and Effectiveness on Film Cooled Turbine Blade Tip Models written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-15 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: A computational study has been performed to predict the distribution of convective heat transfer coefficient on a simulated blade tip with cooling holes. The purpose of the examination was to assess the ability of a three-dimensional Reynolds-averaged Navier-Stokes solver to predict the rate of tip heat transfer and the distribution of cooling effectiveness. To this end, the simulation of tip clearance flow with blowing of Kim and Metzger was used. The agreement of the computed effectiveness with the data was quite good. The agreement with the heat transfer coefficient was not as good but improved away from the cooling holes. Numerical flow visualization showed that the uniformity of wetting of the surface by the film cooling jet is helped by the reverse flow due to edge separation of the main flow. Ameri, A. A. and Rigby, D. L. Glenn Research Center NASA/CR-1999-209165, NAS 1.26:209165, E-11756