Download or read book The Effect of Journal Roughness and Foil Coatings on the Performance of Heavily Loaded Foil Air Bearings written by and published by . This book was released on 2001 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: Foil air bearing load capacity tests were conducted to investigate if a solid lubricant coating applied to the surface of the bearing's top foil can function as a break-in coating. Two foil coating materials, a conventional soft polymer film (polyimide) and a hard ceramic (alumina), were independently evaluated against as-ground and worn (run-in) journals coated with NASA PS304, a high-temperature solid lubricant composite coating. The foil coatings were evaluated at journal rotational speeds of 30000 rpm and at 25 deg C. Tests were also performed on a foil bearing with a bare (uncoated) nickel-based superalloy top foil to establish a baseline for comparison. The test results indicate that the presence of a top foil solid lubricant coating is effective at increasing the load capacity performance of the foil bearing. Compared to the uncoated baseline, the addition of the soft polymer coating on the top foil increased the bearing load coefficient by 120 percent when operating against an as-ground journal surface and 85 percent against a run-in journal surface. The alumina coating increased the load coefficient by 40 percent against the as-ground journal but did not have any affect when the bearing was operated with the run-in journal. The results suggest that the addition of solid lubricant films provide added lubrication when the air film is marginal indicating that as the load capacity is approached foil air bearings transition from hydrodynamic to mixed and boundary lubrication.
Download or read book The effect of journal roughness and foil coatings written by and published by DIANE Publishing. This book was released on with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Systems Approach to the Solid Lubrication of Foil Air Bearings for Oil Free Turbomachinery written by and published by . This book was released on 2002 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book 15th Wear of Materials written by Peter J. Blau and published by Elsevier. This book was released on 2005-10-03 with total page 826 pages. Available in PDF, EPUB and Kindle. Book excerpt: These proceedings of the 15th International Conference on Wear of Materials focus on the friction and wear of materials in various applications under different environments from the nanometer scale to the meter scale. The conference provides a unique international forum for researchers and practitioners from different disciplines to exchange latest results. Coverage includes: . Wear assessment and monitoring . Wear modeling, mechanisms, mapping and prediction . Wear-corrosion testing and control . Surface engineering for wear and wear-corrosion control . Development of new wear test methods and wear test methodologies . Wear of materials for biomedical applications . Wear of non-equilibrium materials: from atomic dimensions to the micro-scale . Wear of hard and superhard materials . Wear of materials in the earthmoving, minerals processing and mining industries
Download or read book Monthly Catalog of United States Government Publications written by and published by . This book was released on 2003 with total page 636 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Journal of Tribology written by and published by . This book was released on 2004 with total page 438 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Proceedings of the World Tribology Congress III 2005 written by and published by . This book was released on 2005 with total page 1040 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NASA Technical Memorandum written by and published by . This book was released on 1979 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fundamentals of Fluid Film Lubrication written by Bernard J. Hamrock and published by CRC Press. This book was released on 2004-03-15 with total page 747 pages. Available in PDF, EPUB and Kindle. Book excerpt: Specifically focusing on fluid film, hydrodynamic, and elastohydrodynamic lubrication, this edition studies the most important principles of fluid film lubrication for the correct design of bearings, gears, and rolling operations, and for the prevention of friction and wear in engineering designs. It explains various theories, procedures, and equations for improved solutions to machining challenges. Providing more than 1120 display equations and an introductory section in each chapter, Fundamentals of Fluid Film Lubrication, Second Edition facilitates the analysis of any machine element that uses fluid film lubrication and strengthens understanding of critical design concepts.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1970 with total page 1338 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Lightning Protection of Aircraft written by Franklin Fisher and published by CreateSpace. This book was released on 2012-07-13 with total page 564 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is an attempt to present under one cover the current state of knowledge concerning the potential lightning effects on aircraft and that means that are available to designers and operators to protect against these effects. The impetus for writing this book springs from two sources- the increased use of nonmetallic materials in the structure of aircraft and the constant trend toward using electronic equipment to handle flight-critical control and navigation function.
Download or read book Annual Research Progress Report written by and published by . This book was released on 1975 with total page 476 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effect of Compositional Tailoring on the Thermal Expansion and Tribological Properties of PS300 A Solid Lubricant Composite Coating written by and published by . This book was released on 1996 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Performance and Durability of High Temperature Foil Air Bearings for Oil Free Turbomachinery written by C. DellaCorte and published by . This book was released on 2000 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt: The performance and durability of advanced, high temperature foil air bearings are evaluated under a wide range (10-50 kPa) of loads at temperatures from 25 to 650 deg C. The bearings are made from uncoated nickel based superalloy foils. The foil surface experiences sliding contact with the shaft during initial start/stop operation. To reduce friction and wear, the solid lubricant coating, PS 304, is applied to the shaft by plasma spraying. PS304 is a NiCr based Cr2O3 coating with silver and barium fluoride/calcium fluoride solid lubricant additions. The results show that the bearings provide lives well in excess of 30,000 cycles under all of the conditions tested. Several bearings exhibited lives in excess of 100,000 cycles. Wear is a linear function of the bearing load. The excellent performance measured in this study suggests that these bearings and the PS 304 coating are well suited for advanced high temperature, oil-free turbomachinery applications.
Download or read book Gas Turbine Engineering Handbook written by Meherwan P. Boyce and published by Elsevier. This book was released on 2017-09-01 with total page 956 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Gas Turbine Engineering Handbook has been the standard for engineers involved in the design, selection, and operation of gas turbines. This revision includes new case histories, the latest techniques, and new designs to comply with recently passed legislation. By keeping the book up to date with new, emerging topics, Boyce ensures that this book will remain the standard and most widely used book in this field. The new Third Edition of the Gas Turbine Engineering Hand Book updates the book to cover the new generation of Advanced gas Turbines. It examines the benefit and some of the major problems that have been encountered by these new turbines. The book keeps abreast of the environmental changes and the industries answer to these new regulations. A new chapter on case histories has been added to enable the engineer in the field to keep abreast of problems that are being encountered and the solutions that have resulted in solving them. - Comprehensive treatment of Gas Turbines from Design to Operation and Maintenance. In depth treatment of Compressors with emphasis on surge, rotating stall, and choke; Combustors with emphasis on Dry Low NOx Combustors; and Turbines with emphasis on Metallurgy and new cooling schemes. An excellent introductory book for the student and field engineers - A special maintenance section dealing with the advanced gas turbines, and special diagnostic charts have been provided that will enable the reader to troubleshoot problems he encounters in the field - The third edition consists of many Case Histories of Gas Turbine problems. This should enable the field engineer to avoid some of these same generic problems
Download or read book Tribology written by and published by . This book was released on 1985 with total page 147 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Facing the Heat Barrier written by T.A. Heppenheimer and published by Courier Dover Publications. This book was released on 2018-09-12 with total page 355 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume from The NASA History Series presents an overview of the science of hypersonics, the study of flight at speeds at which the physics of flows is dominated by aerodynamic heating. The survey begins during the years immediately following World War II, with the first steps in hypersonic research: the development of missile nose cones and the X-15; the earliest concepts of hypersonic propulsion; and the origin of the scramjet engine. Next, it addresses the re-entry problem, which came to the forefront during the mid-1950s, showing how work in this area supported the manned space program and contributed to the development of the orbital shuttle. Subsequent chapters explore the fading of scramjet studies and the rise of the National Aerospace Plane (NASP) program of 1985–95, which sought to lay groundwork for single-stage vehicles. The program's ultimate shortcomings — in terms of aerodynamics, propulsion, and materials — are discussed, and the book concludes with a look at hypersonics in the post-NASP era, including the development of the X-33 and X-34 launch vehicles, further uses for scramjets, and advances in fluid mechanics. Clearly, ongoing research in hypersonics has yet to reach its full potential, and readers with an interest in aeronautics and astronautics will find this book a fascinating exploration of the field's history and future.
