Download or read book Design Study of Wafer Seals for Future Hypersonic Vehicles written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-24 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: Future hypersonic vehicles require high temperature, dynamic seals in advanced hypersonic engines and on the vehicle airframe to seal the perimeters of movable panels, flaps, and doors. Current seals do not meet the demanding requirements of these applications, so NASA Glenn Research Center is developing improved designs to overcome these shortfalls. An advanced ceramic wafer seal design has shown promise in meeting these needs. Results from a design of experiments study performed on this seal revealed that several installation variables played a role in determining the amount of leakage past the seals. Lower leakage rates were achieved by using a tighter groove width around the seals, a higher seal preload, a tighter wafer height tolerance, and a looser groove length. During flow testing, a seal activating pressure acting behind the wafers combined with simulated vibrations to seat the seals more effectively against the sealing surface and produce lower leakage rates. A seal geometry study revealed comparable leakage for full-scale wafers with 0.125 and 0.25 in. thicknesses. For applications in which lower part counts are desired, fewer 0.25-in.-thick wafers may be able to be used in place of 0.125-in.-thick wafers while achieving similar performance. Tests performed on wafers with a rounded edge (0.5 in. radius) in contact with the sealing surface resulted in flow rates twice as high as those for wafers with a flat edge. Half-size wafers had leakage rates approximately three times higher than those for full-size wafers. Dunlap, Patrick H. and Finkbeiner, Joshua R. and Steinetz, Bruce M. and DeMange, Jeffrey J. Glenn Research Center NASA/TM-2005-213858, E-15228, AIAA Paper 2005-4153
Download or read book Design Study of Wafer Seals for Future Hypersonic Vehicles written by and published by . This book was released on 2005 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Further Investigations of Hypersonic Engine Seals written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-21 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: Durable, flexible sliding seals are required in advanced hypersonic engines to seal the perimeters of movable engine ramps for efficient, safe operation in high heat flux environments at temperatures of 2000 to 2500 F. Current seal designs do not meet the demanding requirements for future engines, so NASA's Glenn Research Center is developing advanced seals and preloading devices to overcome these shortfalls. An advanced ceramic wafer seal design and two silicon nitride compression spring designs were evaluated in a series of compression, scrub, and flow tests. Silicon nitride wafer seals survived 2000 in. (50.8 m) of scrubbing at 2000 F against a silicon carbide rub surface with no chips or signs of damage. Flow rates measured for the wafers before and after scrubbing were almost identical and were up to 32 times lower than those recorded for the best braided rope seal flow blockers. Silicon nitride compression springs showed promise conceptually as potential seal preload devices to help maintain seal resiliency. Dunlap, Patrick H., Jr. and Steinetz, Bruce M. and DeMange, Jeffrey J. Glenn Research Center NASA/TM-2004-213188, E-14687, AIAA Paper 2004-3887
Download or read book High Temperature Propulsion System Structural Seals for Future Space Launch Vehicles written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-21 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: Durable, flexible sliding seals are required in advanced hypersonic engines to seal the perimeters of movable engine ramps for efficient, safe operation in high heat flux environments at temperatures of 2000 to 2500 F. Current seal designs do not meet the demanding requirements for future engines, so NASA s Glenn Research Center is developing advanced seals and preloading devices to overcome these shortfalls. An advanced ceramic wafer seal design and two types of seal preloading devices were evaluated in a series of compression, scrub, and flow tests. Silicon nitride wafer seals survived 2000 in. 1000 cycles) of scrubbing at 1600 F against an Inconel 625 rub surface with no chips or signs of damage. Flow rates measured for the wafers before and after scrubbing were almost identical and were up to 32 times lower than those recorded for the best braided rope seal flow blockers. Canted coil springs and silicon nitride compression springs showed promise conceptually as potential seal preloading devices to help maintain seal resiliency. A finite element model of the canted coil spring revealed that it should be possible to produce a spring out of high temperature materials for applications at 2000+ F. Dunlap, Patrick H., Jr. and Steinetz, Bruce M. and DeMange, Jeffrey J. Glenn Research Center NASA/TM-2004-212907, E-14304
Download or read book 41st AIAA ASME SAE ASEE Joint Propulsion Conference Exhibit 10 13 July 2005 Tucson Arizona 05 4150 05 4199 written by and published by . This book was released on 2005 with total page 714 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advanced Control Surface Seal Development for Future Space Vehicles written by J. J. Demange and published by BiblioGov. This book was released on 2013-06 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: NASA s Glenn Research Center (GRC) has been developing advanced high temperature structural seals since the late 1980's and is currently developing seals for future space vehicles as part of the Next Generation Launch Technology (NGLT) program. This includes control surface seals that seal the edges and hinge lines of movable flaps and elevons on future reentry vehicles. In these applications, the seals must operate at temperatures above 2000 F in an oxidizing environment, limit hot gas leakage to protect underlying structures, endure high temperature scrubbing against rough surfaces, and remain flexible and resilient enough to stay in contact with sealing surfaces for multiple heating and loading cycles. For this study, three seal designs were compared against the baseline spring tube seal through a series of compression tests at room temperature and 2000 F and flow tests at room temperature. In addition, canted coil springs were tested as preloaders behind the seals at room temperature to assess their potential for improving resiliency. Addition of these preloader elements resulted in significant increases in resiliency compared to the seals by themselves and surpassed the performance of the baseline seal at room temperature. Flow tests demonstrated that the seal candidates with engineered cores had lower leakage rates than the baseline spring tube design. However, when the seals were placed on the preloader elements, the flow rates were higher as the seals were not compressed as much and therefore were not able to fill the groove as well. High temperature tests were also conducted to asses the compatibility of seal fabrics against ceramic matrix composite (CMC) panels anticipated for use in next generation launch vehicles. These evaluations demonstrated potential bonding issues between the Nextel fabrics and CMC candidates.
Download or read book Research Technology 2004 written by and published by DIANE Publishing. This book was released on with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book High Temperature Performance Evaluation of a Hypersonic Engine Ceramic Wafer Seal written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-05 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: Leakage rates of an innovative hypersonic engine seal were measured using a specially developed static high temperature seal test fixture at NASA Lewis Research Center. The three foot long structural panel-edge seal is designed to minimize leakage of high temperature, high pressure gases past the movable panels of advanced ramjet/scramjet engines. The seal is made of a stack of precision machined ceramic wafer pieces that are inserted into a closely conforming seal channel in the movable engine panel. The wafer seal accommodates the significant distortions in the adjacent engine walls through relative sliding between adjacent wafers. Seal leakage rates are presented for engine simulated air temperatures up to 1350 F and for engine pressures up to 100 psi. Leakage rates are also presented for the seal, sealing both a flat wall condition, and an engine simulated distorted wall condition in which the distortion was 0.15 in. in only an 18 in. span. Seal leakage rates were low, meeting an industry-established tentative leakage limit for all combinations of temperature, pressure, and wall conditions considered. Comparisons are made between the measured leakage rates and leakage rates predicted using a seal leakage model developed from externally-pressurized gas film bearing theory. Steinetz, Bruce M. Glenn Research Center RTOP 505-63-5B...
Download or read book Toward an Improved Hypersonic Engine Seal written by and published by . This book was released on 2003 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Toward an Improved Hypersonic Engine Seal written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-20 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: High temperature, dynamic seals are required in advanced engines to seal the perimeters of movable engine ramps for efficient, safe operation in high heat flux environments at temperatures from 2000 to 2500 F. Current seal designs do not meet the demanding requirements for future engines, so NASA s Glenn Research Center (GRC) is developing advanced seals to overcome these shortfalls. Two seal designs and two types of seal preloading devices were evaluated in a series of compression tests at room temperature and 2000 F and flow tests at room temperature. Both seals lost resiliency with repeated load cycling at room temperature and 2000 F, but seals with braided cores were significantly more flexible than those with cores composed of uniaxial ceramic fibers. Flow rates for the seals with cores of uniaxial fibers were lower than those for the seals with braided cores. Canted coil springs and silicon nitride compression springs showed promise conceptually as potential seal preloading devices to help maintain seal resiliency. Dunlap, Patrick H., Jr. and Steinetz, Bruce M. and DeMange,Jeffrey J. and Taylor, Shawn C. Glenn Research Center NASA/TM-2003-212531, E-14093, NAS 1.15:212531, AIAA Paper 2003-4834
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1994 with total page 716 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Evaluation of an Innovative High Temperature Ceramic Wafer Seal for Hypersonic Engine Applications written by Bruce M. Steinetz and published by . This book was released on 1991 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NASA SP written by and published by . This book was released on 1992 with total page 654 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Proceedings of the 2022 International Conference on Smart Manufacturing and Material Processing SMMP2022 written by A. Nayyar and published by IOS Press. This book was released on 2022-11-29 with total page 278 pages. Available in PDF, EPUB and Kindle. Book excerpt: Smart manufacturing is a broad category of manufacturing that employs computer-integration, high levels of adaptability and rapid design changes, together with digital information technology and a technically-trained workforce. This book presents the proceedings of SMMP2022, the 2022 International Conference on Smart Manufacturing and Material Processing, held on 12 and 13 August 2022 as a virtual event due to continuing restrictions related to the COVID-19 pandemic, and hosted from Shanghai, China. The conference provides a platform for researchers and scientists from smart manufacturing and material sciences to come together with researchers from various other application areas to discuss problems and solutions, identify new issues, and shape future directions for research. The conference received 60 submissions. These were submitted to a rigorous peer review process by a committee of experts from various disciplines, after which, 23 were accepted for presentation at the conference and publication here. The topics covered include materials processing and product manufacture, sensors and smart material systems, functional materials, industrial automation and process control, and discussion of the state-of-the-art and future direction of smart manufacturing and material sciences. Providing an overview of current developments in smart manufacturing and material processing, the book will be of interest to all those working in the field.
Download or read book Monthly Catalog of United States Government Publications written by and published by . This book was released on 1995 with total page 1482 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Aeronautical Engineering written by and published by . This book was released on 1991 with total page 538 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Monthly Catalogue United States Public Documents written by and published by . This book was released on 1995 with total page 1484 pages. Available in PDF, EPUB and Kindle. Book excerpt:
