Download or read book Endwall Profiling for the Reduction of Secondary Flow in Turbines written by Grant Laidlaw Ingram and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Application of Non axisymmetric Endwall Contouring in a 1 1 written by Glen Campbell Snedden and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Today gas turbines are a crucial part of the global power generation and aviation industries. Small improvements to the efficiencies of individual components within the gas flow path can, over time, lead to dramatic cost savings for the operator and at the same time improve on the amount of carbon dioxide gas emissions to the environment. One such technology is the reduction of secondary flow losses in individual blade rows within the compressor or turbine section of the gas turbine through the use of non-axisymmetric endwall contouring. By introducing subtle geometrical features onto the endwall it has been shown to be possible to improve the efficiency of individual blade rows by between 1 and 2%. Few studies of these non-axisymmetric endwalls have been performed outside of the two dimensional cascade and computational domain, in addition these endwalls have been designed and tested to improve the performance of blade rows at a single design point with the off design performance having been ignored. The work presented here is aimed at investigating the use of such endwalls in a rotating blade row both at design and off-design conditions and in the presence of an upstream blade row. To this end a 1 1/2 stage, low speed, turbine test rig has been refurbished and a new set of blades was designed to accommodate the profile of the Durham cascade at the hub. The Durham cascade is a de facto industry test case for non-axisymmetric endwall applications and therefore a generic, cascade proven, endwall design is available from the literature. The design of this new blade set is unique in that it is openly available. The results include steady-state 5-hole pressure probe measurements between blade rows and computational fluid dynamics solutions to provide detailed analysis of the flow quality found within the turbine. These results are reproduced for a turbine with annular or reference endwalls and one with the generic P2 endwall design obtained from the Durham cascade. Experimentally a 1.5% improvement in mixed out stage efficiency at the design condition has been found with a positive trend with increasing load. Additionally the rotor exit flows are show to be generally more uniform in the presence of profiled endwalls. The rotor torque is however reduced by as much as 3.5% and the improved flow uniformity does not always translate into a improved performance in the downstream row. Insight into the overall performance and fluid mechanics of the generic non-axisymmetric endwall at a variety of load conditions has been gained and an analysis of the parameters commonly used in optimising these endwalls is discussed with Cske being clearly shown to be the superior parameter in this case. CFD evidence suggests that while the cross passage pressure gradient is reduced by endwall profiling the extent of the effect of the change in hub endwalls reaches as far as the tip. The mechanism by which the overall loss is reduced appears to be a through a change in the relative strengths of the suction and pressure side horseshoe vortices and through the delayed migration of the passage cross flow, this change the relationship of these two vortex structures; dispersing the vortex structures as they leave the row and reducing the potential for mixing losses downstream.
Download or read book Secondary flow reduction in a nozzle guide vane cascade by non axisymmetric end wall profiling ASME 99 GT 339 written by J. Yan 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, Jun 7-Jun 10, 1999.
Download or read book Endwall Profiling in Axial Flow Turbines written by M. J. Atkins and published by . This book was released on 1984 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Secondary Flow Reduction in Nozzle Guide Vane Cascade by Non axisymmetric End wall Profiling written by J. Yan and published by . This book was released on 1999 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Secondary Flow Loss Reduction in Highly Loaded Turbines written by Sandor Becz and published by . This book was released on 2007 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Axial Turbine Aerodynamics for Aero engines written by Zhengping Zou and published by Springer. This book was released on 2018-01-11 with total page 572 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a monograph on aerodynamics of aero-engine gas turbines focusing on the new progresses on flow mechanism and design methods in the recent 20 years. Starting with basic principles in aerodynamics and thermodynamics, this book systematically expounds the recent research on mechanisms of flows in axial gas turbines, including high pressure and low pressure turbines, inter-turbine ducts and turbine rear frame ducts, and introduces the classical and innovative numerical evaluation methods in different dimensions. This book also summarizes the latest research achievements in the field of gas turbine aerodynamic design and flow control, and the multidisciplinary conjugate problems involved with gas turbines. This book should be helpful for scientific and technical staffs, college teachers, graduate students, and senior college students, who are involved in research and design of gas turbines.
Download or read book Reduction of Secondary Flow Losses in a Turbine for Use in Man portable Power Generation written by Andrew J. Yatsko and published by . This book was released on 2014 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt: As the world has moved into a more energy-demanding environment, there has been the push for higher energy density in a smaller package. One of the potential solutions is through the application of a gas turbine engine; yet the challenge is extracting the energy efficiently through the small components. The focus of the research is on the turbine components and how secondary flow losses from generated airfoil shapes can be reduced to improve component performance. One of the secondary flow loss items to be addressed is the generation of the Horseshoe Vortex. The Horseshoe Vortex is an aerodynamic phenomenon that occurs in axial turbine cascades that degrades the aerodynamic performance. This research will show that through airfoil design optimization, the Horseshoe Vortex on small turbine nozzles can be reduced. The initial turbine design was generated using simple imcompressible flow calculations and then run through a Navier-Strokes SST solver. This solver allows for the interaction of the boundary layer with the airfoil geometry, therefore generating a new set of inlet velocity triangles. The geometry was then optimized to match the new inlet velocity triangle. The new optimized airfoil was run through the same boundary layer build up, and the same boundary conditions as the original incompressible design. The presented results will show that the Horseshoe Vortex has been mitigated and that the total pressure distribution at the exit of the turbine inlet nozzle cascade has improved by 7.6%.
Download or read book Secondary Flow Reduction Techniques in Linear Turbine Cascades written by Thomas Ernst Biesinger and published by . This book was released on 1993 with total page 426 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book On the Experimental Evaluation of Loss Production and Reduction in a Highly Loaded Low Pressure Turbine Cascade written by Philip Steven Bear and published by . This book was released on 2016 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt: Improvements in turbine design methods have resulted in the development of blade profiles with both high lift and good Reynolds lapse characteristics. An increase in aerodynamic loading of blades in the low pressure turbine section of aircraft gas turbine engines has the potential to reduce engine weight or increase power extraction. Increased blade loading means larger pressure gradients and increased secondary losses near the endwall. Prior work has emphasized the importance of reducing these losses if highly loaded blades are to be utilized. The present study analyzes the secondary flow field of the front-loaded low-pressure turbine blade designated L2F with and without blade profile contouring at the junction of the blade and endwall. The current work explores the loss production mechanisms inside the low pressure turbine cascade. Stereoscopic particle image velocimetry data, total pressure loss data and oil flow visualization are used to describe the secondary flow field. The flow is analyzed in terms of total pressure loss, vorticity, Q-Criterion, Reynolds' stresses, turbulence intensity and turbulence production. The flow description is then expanded upon using an Implicit Large Eddy Simulation of the flow field. The RANS momentum equations contain terms with static pressure derivatives. With some manipulation these equations can be rearranged to form an equation for the change in total pressure along a streamline as a function of velocity only. After simplifying for the flow field in question the equation can be interpreted as the total pressure transport along a streamline. A comparison of the total pressure transport calculated from the velocity components and the total pressure loss is presented and discussed. Peak values of total pressure transport overlap peak values of total pressure loss through and downstream of the passage suggesting that total pressure transport is a useful tool for localizing and predicting loss origins and loss development using velocity data which can be obtained non-intrusively.
Download or read book Secondary Flows and Endwall Boundary Layers in Axial Turbomachines written by and published by . This book was released on 1984 with total page 534 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Gas Turbine Heat Transfer and Cooling Technology Second Edition written by Je-Chin Han and published by CRC Press. This book was released on 2012-11-27 with total page 892 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive reference for engineers and researchers, Gas Turbine Heat Transfer and Cooling Technology, Second Edition has been completely revised and updated to reflect advances in the field made during the past ten years. The second edition retains the format that made the first edition so popular and adds new information mainly based on selected published papers in the open literature. See What’s New in the Second Edition: State-of-the-art cooling technologies such as advanced turbine blade film cooling and internal cooling Modern experimental methods for gas turbine heat transfer and cooling research Advanced computational models for gas turbine heat transfer and cooling performance predictions Suggestions for future research in this critical technology The book discusses the need for turbine cooling, gas turbine heat-transfer problems, and cooling methodology and covers turbine rotor and stator heat-transfer issues, including endwall and blade tip regions under engine conditions, as well as under simulated engine conditions. It then examines turbine rotor and stator blade film cooling and discusses the unsteady high free-stream turbulence effect on simulated cascade airfoils. From here, the book explores impingement cooling, rib-turbulent cooling, pin-fin cooling, and compound and new cooling techniques. It also highlights the effect of rotation on rotor coolant passage heat transfer. Coverage of experimental methods includes heat-transfer and mass-transfer techniques, liquid crystal thermography, optical techniques, as well as flow and thermal measurement techniques. The book concludes with discussions of governing equations and turbulence models and their applications for predicting turbine blade heat transfer and film cooling, and turbine blade internal cooling.
Download or read book Controlling the secondary flow in a turbine cascade by 3D airfoil design and endwall contouring ASME 98 GT 72 written by Arno Duden and published by . This book was released on 1998 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presented at the International Gas Turbine & Aeroengine Congress & Exhibition, Stockholm, Sweden, June 2 - June 5, 1998.
Download or read book Effect of Inlet Conditions on Endwall Secondary Flows written by Kristina S. Hermanson and published by . This book was released on 1999 with total page 474 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Influence of Purge Flow on Performance of an End Wall Profiled Turbine written by Peter Schüpbach and published by Sudwestdeutscher Verlag Fur Hochschulschriften AG. This book was released on 2010-03 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt: The goal of this study is the investigation of the promising secondary flow control technique of non-axisymmetric end wall profiling in a more engine representative environment. In this work end wall profiling is applied to the first stage of a high work, 1.5 stage, unshrouded turbine. Without purge flow non-axisymmetric end wall profiling has demonstrated a considerable increase of total-to-total efficiency. The two designs increased the total-to-total efficiency by 1% and 0.3% respectively relative to a baseline efficiency of already 91%. The first end wall design having the highest efficiency without purge flow shows the highest efficiency drop of 1.2% per injected massflow percent if purge flow is applied. The second end wall design and the baseline case show comparable sensitivities with -0.7%/% and -0.6%/% to purge flow. The reason for the increased sensitivity of the first design is an increased circumferential pressure gradient at the first vane rim compared to the baseline case and the second end wall design. Resulting in the strongest injection jets and therefore in more induced vorticity.
Download or read book The secondary flow field of a turbine cascade with 3D airfoil design and endwall contouring at off design incidence ASME 99 GT 211 written by Arno Duden 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-June 10, 1999.
Download or read book Comparison of Secondary Flows and Boundary layer Accumulations in Several Turbine Nozzles written by Milton G. Kofskey and published by . This book was released on 1953 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt: An investigation of secondary-flow loss cores originating in turbine nozzle blade passages was conducted by means of flow visualization studies and detailed flow measurements. The degree of which blade surface velocity profiles affect the magnitude and concentration of loss cores was investigated by comparing three nozzle blade configurations.
