Download or read book The Effect of a Diffuser on the Characteristic of Stable Operation of a Centrifugal Compressor Stage written by N. L. Zeldes and published by . This book was released on 1971 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt: Experimental results are presented from studies of stages of centrifugal compressors with different diffusors in relation to geometric characteristics of channels and grids with the number of vanes and vane placement angle are varied. A well defined analytic relationship has been established between the onset of flow separation with the moment of equality of the average flow angle at the outlet from the ring with intake angles of diffusor vane placement. Recording of the moment of onset of separation by oscillography and study of flow formation in the gap behind the ring with a pneumo probe confirmed the conclusion of constancy of flow angle in separation independently of rotor revolutions and affords tracking the analytic and experimental limits of separation for satisfactory agreement.

Download or read book Characterization of Performance limiting Flow Mechanisms in a Centrifugal Compressor Stage written by David W. Erickson (S.M.) and published by . This book was released on 2017 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt: This research characterizes the performance of a centrifugal compressor stage with a special focus on the pipe diffuser. Two diffuser configurations are studied, one of which is a truncated version of the other. Experimental data acquired on a research compressor stage is interrogated along with a set of well-designed Reynolds-Averaged Navier Stokes computations, complemented by reduced order flow modeling. The fundamental performance-limiting flow mechanisms in the diffuser are identified and used to physically relate important geometry features and operating conditions to the observed compressor pressure rise, efficiency, and operability characteristics. Despite large differences in their geometry, the two diffuser configurations exhibit similar pressure recovery characteristics due to differences in exit nonuniformity and flow angle which result in similar effective area ratios. Variations in the diffuser pressure recovery coefficient with operating point are found to be most influenced by the diffuser inlet flow angle, and secondly by the inlet Mach number. The diffuser inlet flow angle has the primary effect of setting the diffuser inlet one-dimensional area ratio, increasing diffusion at high flow angles. In addition, the diffuser incidence angle influences the formation of counter-rotating vortex pairs that persist throughout the diffuser passage. Using a two-dimensional integral boundary layer model that is modified to accommodate three-dimensional effects as source terms, these secondary flows are shown to detrimentally impact the diffuser pressure rise capability by accumulating high loss flow along the diffuser wall near the plane of symmetry between the vortices. This contributes to the extent and location of a large diffuser passage separation, especially for the baseline diffuser. The impact of the vortices on the boundary layer growth rate is shown to scale inversely with diffuser aspect ratio. The major performance difference between the two diffuser configurations is that the truncated diffuser configuration experiences enhanced stall margin over the baseline diffuser at the design speed. These differences are traced to reduced secondary flows influence and thus reduced separation extent for the higher aspect ratio truncated diffuser. It is hypothesized that the onset of stall for the baseline diffuser configuration is initiated by the transition of the vortex location and corresponding passage separation between diffuser pressure and suction sides with increasing cusp incidence. Conversely, because the extent of the passage separation in the truncated diffuser is diminished due to the higher aspect ratio, the switch in separation side does not immediately initiate instability. The fact that secondary flows have a large influence on diffuser pressure rise capability and compressor stability is counter to conventional preliminary diffuser design approaches which neglect such 3D effects. The findings of this research may therefore be considered during preliminary design optimization to produce better-performing diffuser designs.

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1978 with total page 790 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.

Download or read book The Effect of Exit vaned Diffusers on Centrifugal compressor Performance written by Frank Florian Szczesny and published by . This book was released on 1962 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Design of High Efficiency Turbomachinery and Gas Turbines second edition with a new preface written by David Gordon Wilson and published by MIT Press. This book was released on 2014-09-05 with total page 625 pages. Available in PDF, EPUB and Kindle. Book excerpt: The second edition of a comprehensive textbook that introduces turbomachinery and gas turbines through design methods and examples. This comprehensive textbook is unique in its design-focused approach to turbomachinery and gas turbines. It offers students and practicing engineers methods for configuring these machines to perform with the highest possible efficiency. Examples and problems are based on the actual design of turbomachinery and turbines. After an introductory chapter that outlines the goals of the book and provides definitions of terms and parts, the book offers a brief review of the basic principles of thermodynamics and efficiency definitions. The rest of the book is devoted to the analysis and design of real turbomachinery configurations and gas turbines, based on a consistent application of thermodynamic theory and a more empirical treatment of fluid dynamics that relies on the extensive use of design charts. Topics include turbine power cycles, diffusion and diffusers, the analysis and design of three-dimensional free-stream flow, and combustion systems and combustion calculations. The second edition updates every chapter, adding material on subjects that include flow correlations, energy transfer in turbomachines, and three-dimensional design. A solutions manual is available for instructors. This new MIT Press edition makes a popular text available again, with corrections and some updates, to a wide audience of students, professors, and professionals.

Download or read book Principles of Turbomachinery written by R. K. Turton and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 213 pages. Available in PDF, EPUB and Kindle. Book excerpt: This text outlines the fluid and thermodynamic principles that apply to all classes of turbomachines, and the material has been presented in a unified way. The approach has been used with successive groups of final year mechanical engineering students, who have helped with the development of the ideas outlined. As with these students, the reader is assumed to have a basic understanding of fluid mechanics and thermodynamics. However, the early chapters combine the relevant material with some new concepts, and provide basic reading references. Two related objectives have defined the scope of the treatment. The first is to provide a general treatment of the common forms of turbo machine, covering basic fluid dynamics and thermodynamics of flow through passages and over surfaces, with a brief derivation of the fundamental governing equations. The second objective is to apply this material to the various machines in enough detail to allow the major design and performance factors to be appreciated. Both objectives have been met by grouping the machines by flow path rather than by application, thus allowing an appreciation of points of similarity or difference in approach. No attempt has been made to cover detailed points of design or stressing, though the cited references and the body of information from which they have been taken give this sort of information. The first four chapters introduce the fundamental relations, and the suc ceeding chapters deal with applications to the various flow paths.

Download or read book The Design of High efficiency Turbomachinery and Gas Turbines written by David Gordon Wilson and published by . This book was released on 1998 with total page 632 pages. Available in PDF, EPUB and Kindle. Book excerpt: One of the only texts to focus on turbomachinery and gas turbines from the 'design' point of view, this volume reviews the necessary thermodynamics, gives extensive design data, provides engine and component illustrations (with comments on good and less-than-good design features), and contains many worked examples - allowing students to produce preliminary designs that can be made and run quickly - as early as Ch. 5. More comprehensive than similar texts, it features a simplified - and more accurate thermodynamic treatment that eliminates the confusing use of 'gamma' and specific heat together, and provides individual full-chapter coverage of axial-flow turbines and compressors and radial-flow versions of the same. *Contains a Brief History of Turbomachinery. *Features a design perspective throughout - and enables students to develop a preliminary design after Ch. 5. *Offers a unified treatment of energy transfer and vector diagrams - focusing on principles that can be applied easily to compressors, pumps, turbines - radial and axial. *Includes specialized chapters that give far more design data than other similar texts - allowing students to produce a design that can be made and r

Download or read book Turbomachinery Fluid Dynamics and Heat Transfer written by Hah and published by CRC Press. This book was released on 1997-02-04 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt: This festschrift in honor of Professor Budugur Lakshminarayana's 60th birthday-based on the proceedings of a symposium on Turbomachinery Fluid Dynamics and Heat Transfer held recently at The Pennsylvania State University, University Park-provides authoritative and conclusive research results as well as new insights into complex flow features found in the turbomachinery used for propulsion, power, and industrial applications. Explaining in detail compressors, heat transfer fields in turbines, computational fluid dynamics, and unsteady flows, Turbomachinery Fluid Dynamics and Heat Transfer covers: Mixing mechanisms, annulus wall boundary layers, and the flow field in transonic turbocompressors The numerical implementation of turbulence models in a computer code Secondary flows, film cooling, and thermal turbulence modeling The visualization method of modeling using liquid crystals Innovative techniques in the computational modeling of compressor and turbine flows measurement in unsteady flows as well as axial flows and compressor noise generation And much more Generously illustrated and containing key bibliographic citations, Turbomachinery Fluid Dynamics and Heat Transfer is an indispensable resource for mechanical, design, aerospace, marine, manufacturing, materials, industrial, and reliability engineers; and upper-level undergraduate and graduate students in these disciplines.

Download or read book Paper written by and published by . This book was released on 2001 with total page 452 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Radial Flow Turbocompressors written by Michael Casey and published by Cambridge University Press. This book was released on 2021-06-10 with total page 789 pages. Available in PDF, EPUB and Kindle. Book excerpt: An introduction to the theory and engineering practice that underpins the component design and analysis of radial flow turbocompressors. Drawing upon an extensive theoretical background and years of practical experience, the authors provide descriptions of applications, concepts, component design, analysis tools, performance maps, flow stability, and structural integrity, with illustrative examples. Features wide coverage of all types of radial compressor over many applications unified by the consistent use of dimensional analysis. Discusses the methods needed to analyse the performance, flow, and mechanical integrity that underpin the design of efficient centrifugal compressors with good flow range and stability. Includes explanation of the design of all radial compressor components, including inlet guide vanes, impellers, diffusers, volutes, return channels, de-swirl vanes and side-streams. Suitable as a reference for advanced students of turbomachinery, and a perfect tool for practising mechanical and aerospace engineers already within the field and those just entering it.

Download or read book ASME Technical Papers written by and published by . This book was released on 2001 with total page 444 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Compressor Performance written by Theodore Gresh and published by Newnes. This book was released on 2001-05-17 with total page 215 pages. Available in PDF, EPUB and Kindle. Book excerpt: Compressor Performance is a reference book and CD-ROM for compressor design engineers and compressor maintenance engineers, as well as engineering students. The book covers the full spectrum of information needed for an individual to select, operate, test and maintain axial or centrifugal compressors. It includes basic aerodynamic theory to provide the user with the "how's" and "why's" of compressor design. Maintenance engineers will especially appreciate the troubleshooting guidelines offered. Includes many example problems and reference data such as gas properties and flow meter calculations to enable easy analysis of compressor performance in practice. Includes companion CD with computer programs.M. Theodore Gresh has been with the Elliot Company in Jeannette, Pennsylvania, since 1975, initially working on the mechanical and aerodynamic design and application of centrifugal compressors.Unrivalled coverage of the theory and practical use of all kinds of compressors in industrial use from an industry-leading company sourceComplete subject reference and learning resource in one stop, suitable for newly graduated engineers and experienced professional reference useIncludes companion CD-ROM

Download or read book Applied Mechanics Reviews written by and published by . This book was released on 1973 with total page 568 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Investigation of Stall Inception in Centrifugal Compressors Using Isolated Diffuser Simulations written by Jonathan Neil Everitt and published by . This book was released on 2010 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt: In compression systems the range of stable operating is limited by rotating stall and/or surge. Two distinct types of stall precursors can be observed prior to these phenomena: the development of long-wavelength modal waves or a short-wavelength, three-dimensional ow breakdown which is typically known as a "spike". The cause of the latter is not well understood; in axial machines it has been suggested that over-tip spillage ow has a significant role, but spikes can also occur in shrouded vaned diffusers of centrifugal compressors, where these flows are not present, suggesting an alternative mechanism may be at play. Unsteady Reynold's Averaged Navier-Stokes simulations are performed for an isolated vaned radial diffusers from a highly loaded centrifugal compressor. Key to their success is the definition of pitchwise "mixed out" averaged inlet conditions derived from the impeller exit flow field from separate single passage stage calculations. This guarantees the relevant flow features are carried into the diffuser model, particularly the spanwise profile of flow angle and total pressure. It is shown that the isolated diffuser model compares well with experimental data and time-averaged, unsteady, full wheel simulations. The stability of the flow is tested via numerical forced response experiments whereby the inlet conditions are perturbed by a total pressure forcing small in temporal and spatial extent. An unstable rotating stall precursor is observed at low diffuser inlet corrected flow, due to the spanwise non-uniform flow angle and total pressure at the diffuser inlet. The radial pressure gradient imposed by the highly swirling bulk flow leads to flow angles in excess of 90 in the shroud endwall flow. This results in shroud-side separation at the diffuser vane leading edge and a region of recirculating ow in the vaneless space. Vorticity shed from the diffuser vane leading edge convects back to the vaneless space and joins the vortical structures within the recirculating flow. This is suggested to lead to spike stall inception.

Download or read book Exergy for A Better Environment and Improved Sustainability 1 written by Fethi Aloui and published by Springer. This book was released on 2018-08-04 with total page 1443 pages. Available in PDF, EPUB and Kindle. Book excerpt: This multi-disciplinary book presents the most recent advances in exergy, energy, and environmental issues. Volume 1 focuses on fundamentals in the field and covers current problems, future needs, and prospects in the area of energy and environment from researchers worldwide. Based on selected lectures from the Seventh International Exergy, Energy and Environmental Symposium (IEEES7-2015) and complemented by further invited contributions, this comprehensive set of contributions promote the exchange of new ideas and techniques in energy conversion and conservation in order to exchange best practices in "energetic efficiency". Included are fundamental and historical coverage of the green transportation and sustainable mobility sectors, especially regarding the development of sustainable technologies for thermal comforts and green transportation vehicles. Furthermore, contributions on renewable and sustainable energy sources, strategies for energy production, and the carbon-free society constitute an important part of this book. Exergy for Better Environment and Sustainability, Volume 1 will appeal to researchers, students, and professionals within engineering and the renewable energy fields.

Download or read book Modern Refrigeration written by and published by . This book was released on 1949 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Concepts in Turbocharging for Improved Efficiency and Emissions Reduction written by Mehrdad Zangeneh and published by SAE International. This book was released on 2014-09-22 with total page 94 pages. Available in PDF, EPUB and Kindle. Book excerpt: Legislative requirements to reduce CO2 emissions by 2020 have resulted in significant efforts by car manufacturers to explore various methods of pollution abatement. One of the most effective ways found so far is by shortening the cylinder stroke and downsizing the engine. This new engine then needs to be boosted, or turbocharged, to create the full and original load torque. Turbocharging has been and will continue to be a key component to the new technologies that will make a positive difference in the next-generation engines of years to come. Concepts in Turbocharging for Improved Efficiency and Emissions Reduction explores the many ways that turbocharging will deliver concrete results in meeting the new realities of sustainable, green transportation. This collection of very focused technical papers, selected by Mehrdad Zangeneh, PhD., a professor of thermo-fluids at University College in London, provides an assessment of several novel designs intended to improve fuel consumption and cap emissions, while maintaining torque at all speeds. The book is divided into four sections, each addressing the most cutting-edge technologies on the market today: o Two-Stage Turbocharging o Variable Geometry Compressors o Unconventional Compressor Configurations o Electrically Assisted Turbocharging