Download or read book The Republic of Nicaragua written by and published by . This book was released on 1977 with total page 75 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Unsteady Aerodynamics Aeromechanics of Multi Stage Turbomachinery Blading written by and published by . This book was released on 2002 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt: An integrated experiment-theory approach included collaboration between Pratt & Whitney, Duke University, and Purdue University. A benchmark-standard multistage transonic research compressor was developed by modifying the Purdue High-Speed Axial Compressor to feature new IGV and stator rows representative of modern high pressure compressors. A quantitative understanding and predictive capability for multi-stage blade row forced response was developed by analytically and experimentally investigating the fundamental flow phenomena. Experiments at Purdue investigated and quantified the interacting blade row unsteady aerodynamics and resulting vane vibration and stress response. Duke University developed a new computationally efficient unsteady aerodynamic analysis of multistage flows associated with flutter and forced response. The inherently small damping of complex higher order modes was addressed by investigating techniques to control the flow induced vibrations. The issue of robustness was also considered.

Download or read book Turbomachine Unsteady Aerodynamics written by J. S. Rao and published by New Age International. This book was released on 1994 with total page 542 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Unsteady Aerodynamics and Aeroelasticity of Turbomachines written by Torsten H. Fransson and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 835 pages. Available in PDF, EPUB and Kindle. Book excerpt: Twenty-one years have passed since the first symposium in this series was held in Paris (1976). Since then there have been meetings in Lausanne (1980), Cambridge (1984), Aachen (1987), Beijing (1989), Notre Dame (1991) and Fukuoka (1994). During this period a tremendous development in the field of unsteady aerodynamics and aeroelasticity in turbomachines has taken place. As steady-state flow conditions become better known, and as blades in the turbomachine are constantly pushed towards lower weight, and higher load and efficiency, the importance of unsteady phenomena appear more clearly. th The 8 Symposium was, as the previous ones, of high quality. Furthermore, it presented the audience with the latest developments in experimental, numerical and theoretical research. More papers than ever before were submitted to the conference. As the organising committee wanted to preserve the uniqueness of the symposium by having single sessions, and thus mingle speakers and audience with different backgrounds in this interdisciplinary field, only a limited number of papers could be accepted. 54 papers were accepted and presented at the meeting, all of which are included in the present proceedings.

Download or read book A Review of Turbomachinery Blade Row Interaction Research written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-28 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt: Analytical and experimental research in the area of unsteady aerodynamics of turbomachinery has conventionally been applied to blading which oscillates when placed in a uniformly flowing fluid. Comparatively less effort has been offered for the study of blading which is subjected to nonuniformities within the flow field. The fluid dynamic environment of a blade-row embedded within multi-stage turbomachines is dominated by such highly unsteady fluid flow conditions. The production of wakes and circumferential pressure variations from adjacent blade-rows causes large unsteady energy transfers between the fluid and the blades. Determination of the forced response of a blade requires the ability to predict the unsteady loads which are induced by these aerodynamic sources. A review of research publications was done to determine recent investigations of the response of turbomachinery blading subjected to aerodynamic excitations. Such excitations are a direct result of the blade-row aerodynamic interaction which occurs between adjacent cascades of blades. The reports and papers reviewed have been organized into areas emphasizing experimental or analytical efforts. Smith, Todd E. Unspecified Center NAS3-25266; RTOP 505-63-1B...

Download or read book Unsteady Aerodynamic Analysis of Flows in Multistage Turbomachinery Using the Time linearized Navier Stokes Equations written by Dmytro M. Voytovych and published by . This book was released on 2004 with total page 278 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Unsteady Flow and Aeroelasticity in Turbomachinery written by Li He and published by Academic Press. This book was released on 2016-03-01 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt: Blade aeroelasticity has long been regarded a distinctive and critical topic in aerospace and turbomachinery design. More recently, research activities have increased in the area of turbomachinery unsteady flows, and whilst the two topics have seemingly different applications, the many links between them give value to a complementary approach. Unsteady Flow and Aeroelasticity in Turbomachinery is the first high level reference to provide detailed, multi-disciplinary discussion of these related topics and their increasing importance in efforts to develop low-emission and low-noise engines and generators. Filling the need for a well-written book to bring together recent research developments, author Li He seeks to take a unified approach, with emphasis given to physical understanding of the various phenomena and relevant modeling issues before discussion of prediction methods and techniques. This unique resource is aimed at those facing unsteady aerodynamic or aeroelastic problems and aims to help engineers and researchers to overcome challenges in academic, industrial R&D and engine design environments. There are other books on unsteady aerodynamics, and aeroelasticity. The uniqueness is in writing a book focused on these topics in turbomachinery. Rare unified coverage of two closely related topics critical to aero-engine and gas turbine development. Full development of key topics from theoretical background to practical problem solving R&D and design environments Authored by a leading expert from the world-renowned University of Oxford Osney Thermo-Fluids Lab, whose research output forms a key part of Rolls-Royce's research strategy

Download or read book Development of a Linearized Unsteady Euler Analysis for Turbomachinery Blade Rows written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-17 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt: A linearized unsteady aerodynamic analysis for axial-flow turbomachinery blading is described in this report. The linearization is based on the Euler equations of fluid motion and is motivated by the need for an efficient aerodynamic analysis that can be used in predicting the aeroelastic and aeroacoustic responses of blade rows. The field equations and surface conditions required for inviscid, nonlinear and linearized, unsteady aerodynamic analyses of three-dimensional flow through a single, blade row operating within a cylindrical duct, are derived. An existing numerical algorithm for determining time-accurate solutions of the nonlinear unsteady flow problem is described, and a numerical model, based upon this nonlinear flow solver, is formulated for the first-harmonic linear unsteady problem. The linearized aerodynamic and numerical models have been implemented into a first-harmonic unsteady flow code, called LINFLUX. At present this code applies only to two-dimensional flows, but an extension to three-dimensions is planned as future work. The three-dimensional aerodynamic and numerical formulations are described in this report. Numerical results for two-dimensional unsteady cascade flows, excited by prescribed blade motions and prescribed aerodynamic disturbances at inlet and exit, are also provided to illustrate the present capabilities of the LINFLUX analysis. Verdon, Joseph M. and Montgomery, Matthew D. and Kousen, Kenneth A. Unspecified Center AXIAL FLOW; COMPUTATIONAL FLUID DYNAMICS; DIFFERENTIAL EQUATIONS; EULER EQUATIONS OF MOTION; INVISCID FLOW; LINEARIZATION; ROTOR BLADES (TURBOMACHINERY); SURFACE PROPERTIES; THREE DIMENSIONAL FLOW; UNSTEADY AERODYNAMICS; AEROACOUSTICS; AERODYNAMIC CONFIGURATIONS; AEROELASTICITY; AIR INTAKES; CASCADE FLOW; CYLINDRICAL BODIES; DUCTS; MATHEMATICAL MODELS; UNSTEADY FLOW...

Download or read book Aerodynamic Inverse Design of Multistage Turbomachinery Blading written by Benedikt Roidl and published by . This book was released on 2008 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: A recently developed inverse method for single blade rows is extended to 2-D and quasi 3-D multi-stage application. In that method, the pressure distribution on the blade surfaces or alternatively, the blade loading and their thickness distribution are specified and the blade shape is sought using a virtual wall movement. The blade walls move with a virtual velocity distribution that is derived from the difference between the current and the target pressure distribution on the blade surfaces. The scheme is fully consistent with the viscous flow assumption and it is implemented into the time accurate solution of the Reynolds-Averaged Navier-Stokes equations that are expressed in an arbitrary Lagrangian-Eulerian (ALE) form to account for mesh movement. A cell-vertex finite volume method of the Jameson type is used to discretize the equations in space; time accurate integration is obtained using dual time stepping. An algebraic Baldwin-Lomax turbulence model is used for turbulence closure. In order to extend the present method to multistage applications a mixing plane approach using flux averaged flow conditions is employed to couple the vane (stator) and blade (rotor) regions and non-reflecting boundary conditions are implemented at the interface between the two regions to account for short distances between blade leading and trailing edges and the corresponding inlet and exit boundaries. The method is validated on two different cases. Finally three different stages are redesigned: The E/TU-3 single stage turbine, the E/TU-4 2.5 stage turbine and the E/CO-5 2.5 stage compressor. For all cases presented in this thesis the blade pressure distributions and pressure loadings, respectively were selected as design variables, and, by modifying the original profile, it was possible to improve the aerodynamic performance.

Download or read book Research on Aero Thermodynamic Distortion Induced Structural Dynamic Response of Multi Stage Compressor Blading written by Sanford Fleeter and published by . This book was released on 1985 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: The flow physics of multi-stage blade row interactions is being investigated. Unique data are being obtained to define the potential and viscous flow interactions and the effect on the aerodynamic forcing function and the unsteady aerodynamics of both rotors and stators. Analytically, a first principles capability to predict the vibrational response of blading is being developed. Also, unsteady viscous flow analyses for aerodynamic forcing response predictions are being developed. Progress during this reporting period include: vane row experiments which investigate fundamental blade row aerodynamics interactions; the identification and modeling of a vortex street structure in the instantaneous rotor wakes; preparations for rotating blade row experiments; the developement and application of a locally analytic numerical method for steady viscous flows; the formulation of an unsteady incompressible viscous thin airfoil theory. Keywords: Unsteady aerodynamics, Aeroelasticity, Forced vibrations, Gas turbines, Turbomachinery.

Download or read book Solution adaptive Calculation of Unsteady Blade Row Interactions in Transonic Turbomachinery written by Scott M. Richardson and published by . This book was released on 1996 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report describes the development of an implicit, viscous method for the solution of the quasi-three-dimensional flow equations for rotor-stator interaction in transonic turbomachinery. The flow algorithm is described, followed by the implicit time-marching scheme, and the one-equation turbulence model. The algorithm is implemented on an unstructured grid arrangement of locally structured micro-blocks called 'patches.' Solution-dependent adaptation is used to refine the grid in regions containing flow features which require enhanced resolution. An overlapped sliding grid interface is used to transfer flow equation information between the respective blade grids. The resulting computational algorithm has been used to perform a number of validation exercises and has been demonstrated on a modern transonic turbine stage. Where possible, these results are compared with experimental data and show the ability of the method to accurately capture the unsteady flow physics in a robust and computationally efficient manner.

Download or read book Aerothermodynamics of Turbomachinery written by Naixing Chen and published by John Wiley & Sons. This book was released on 2010-06-21 with total page 476 pages. Available in PDF, EPUB and Kindle. Book excerpt: Computational Fluid Dynamics (CFD) is now an essential and effective tool used in the design of all types of turbomachine, and this topic constitutes the main theme of this book. With over 50 years of experience in the field of aerodynamics, Professor Naixing Chen has developed a wide range of numerical methods covering almost the entire spectrum of turbomachinery applications. Moreover, he has also made significant contributions to practical experiments and real-life designs. The book focuses on rigorous mathematical derivation of the equations governing flow and detailed descriptions of the numerical methods used to solve the equations. Numerous applications of the methods to different types of turbomachine are given and, in many cases, the numerical results are compared to experimental measurements. These comparisons illustrate the strengths and weaknesses of the methods – a useful guide for readers. Lessons for the design of improved blading are also indicated after many applications. Presents real-world perspective to the past, present and future concern in turbomachinery Covers direct and inverse solutions with theoretical and practical aspects Demonstrates huge application background in China Supplementary instructional materials are available on the companion website Aerothermodynamics of Turbomachinery: Analysis and Design is ideal for senior undergraduates and graduates studying in the fields of mechanics, energy and power, and aerospace engineering; design engineers in the business of manufacturing compressors, steam and gas turbines; and research engineers and scientists working in the areas of fluid mechanics, aerodynamics, and heat transfer. Supplementary lecture materials for instructors are available at www.wiley.com/go/chenturbo

Download or read book Turbomachinery Flow Physics and Dynamic Performance written by Meinhard T. Schobeiri and published by Springer Science & Business Media. This book was released on 2004-11-12 with total page 535 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past three decades turbomachines experienced a steep increase in efficiency and performance. Based on fundamental principles of turbomachinery thermo-fluid mechanics, numerous CFD based calculation methods are being developed to simulate the complex 3-dimensional, highly unsteady turbulent flow within turbine or compressor stages. The objective of this book is to present the fundamental principals of turbomachinery fluid-thermodynamic design process of turbine and compressor components, power generation and aircraft gas turbines in a unified and compact manner. The book provides senior undergraduate students, graduate students and engineers in the turbomachinery industry with a solid background of turbomachinery flow physics and performance fundamentals that are essential for understanding turbomachinery performance and flow complexes.

Download or read book A Coupled Mode Analysis of Unsteady Multistage Flows in Turbomachinery written by Peter D. Silkowski and published by . This book was released on 1997 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presented at the International Gas Turbine & Aeroengine Congress & Exhibition, Orlando, FL, Jun 2 - Jun 5, 1997.

Download or read book Unsteady Flow in Turbomachinery written by Ronald Mailach and published by . This book was released on 2010 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: The main source of unsteadiness in the stable operating range of turbomachinery is the aerodynamical interaction of the rotor and stator rows. The blades and vanes, moving relatively to each other, interact due to viscous wakes, secondary flow phenomena as well as potential effects. As a result of this, the real flow field is highly periodically unsteady and very complex, especially in multistage engines. These effects are not yet typically addressed in current design systems of turbomachinery. It is therefore a challenge to include beneficial unsteady and secondary flow effects to improve the engine performance. This requires a detailed physical understanding of the flow field as well as the resulting influences on performance and flow stability. The present work focuses on the effects appearing in multistage axial compressors. Different aspects of blade row interactions in a four-stage low-speed compressor are discussed in comparison to the existing physical understanding. This includes experimental results on the periodical unsteady flow field within the axial gaps between the blade rows as well as the flow field within the rotor blade passages. Furthermore, the unsteady behaviour of the blade boundary layer is considered. Other discussed aspects are the influence of wakes and potential effects on the unsteady profile pressures and the excited blade pressure forces. With this work a comprehensive picture on the different features of blade row interaction is drawn."--Back cover.

Download or read book Turbomachines written by and published by . This book was released on 2006 with total page 459 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Computations of Unsteady Multistage Turbomachinery Flows written by Karen L. Gundy-Burlet and published by . This book was released on 1991 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt: