Download or read book Experimental Rotordynamic Coefficient Results for Honeycomb Seals 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 166 pages. Available in PDF, EPUB and Kindle. Book excerpt: Test results (leakage and rotordynamic coefficients) are presented for seven honeycomb-stator smooth-rotor seals. Tests were carried out with air at rotor speeds up to 16,000 cpm and supply pressures up to 8.2 bars. Test results for the seven seals are compared, and the most stable configuration is identified based on the whirl frequency ratio. Results from tests of a smooth-rotor/smooth-stator seal, a teeth-on-stator labyrinth seal, and the most stable honeycomb seal are compared. Elrod, David A. and Childs, Dara W. Unspecified Center AERODYNAMIC COEFFICIENTS; HONEYCOMB STRUCTURES; LABYRINTH SEALS; LEAKAGE; ROTOR AERODYNAMICS; STATORS; COMPARISON; TABLES (DATA); TEST EQUIPMENT...

Download or read book Experimental Rotordynamic Coefficient Results for written by Elias Antonio Soto Azuaje and published by . This book was released on 1997 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Experimental and Theoretical Rotordynamic Coefficients and Leakage of Straight Smooth Annular Gas Seals written by Bradley Gray Kerr and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Results are presented for experimental and theoretical rotordynamic coefficients and leakage of straight smooth annular gas seals. Experimental rotordynamic coefficients were measured and trends in changes of rotordynamic coefficients with operating variables such as rotor speed, back-pressure, fluid preswirl, and seal clearance are analyzed. Experimental results show that cross-coupled stiffness coefficients are highly influenced by fluid preswirl and only moderately influenced by other operating parameters, whereas direct damping is nearly unaffected by changes in operating parameters. Effective damping, a good indicator of stability, is highly affected by fluid preswirl. Although rotordynamic coefficients of straight smooth annular gas seals are assumed to be frequency independent, experimental results suggest a frequency dependent nature at high back-pressures and high excitation frequencies. Experimental results for rotordynamic coefficients and leakage are compared with theoretical predictions of ISOTSEAL, an isothermal-flow, two-control-volume, bulk-flow rotordynamic analysis program. All rotordynamic coefficients are underpredicted. Direct stiffness is poorly predicted while cross-coupled stiffness and direct damping are predicted reasonably well. Leakage is also consistently under-predicted. Theory predicts a slight frequency dependent nature for a limited number of test configurations.

Download or read book Experimental rotordynamic coefficient results for a a labyrinth seal with and without shunt injection and b a honeycomb seal ASME 98 GT 8 written by Dara W. Childs 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 A Comparison of Experimental Results and Theoretical Predictions for the Rotordynamic Coefficients of Short L D written by Joseph Michael Pelletti and published by . This book was released on 1990 with total page 426 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Comparison of Experimental Rotordynamic Coefficient and Static Characteristic Results for Hole pattern Damper Seals and a Honeycomb Seal written by Zeping Yu and published by . This book was released on 1996 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Experimental Measurements and Methods for Data Analysis to Determine the Rotordynamic Coefficients of a Labyrinth Seal written by Sang Kyu Choi and published by . This book was released on 1988 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Comparison of Experimental and Theoretical Results for Rotordynamic Coefficients for Labyrinth Gas Seals written by Joseph Kirk Scharrer and published by . This book was released on 1985 with total page 250 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1994 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Rotordynamic Instability Problems in High Performance Turbomachinery 1996 written by and published by . This book was released on 1997 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Comparison of Experimental Results and Theoretical Predictions for the Rotordynamic Coefficients of Stepped Annular Gas Seals written by Mark Stephen Dunn and published by . This book was released on 1990 with total page 452 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Bearing Dynamic Coefficients in Rotordynamics written by Lukasz Brenkacz and published by John Wiley & Sons. This book was released on 2021-04-05 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt: A guide to bearing dynamic coefficients in rotordynamics that includes various computation methods Bearing Dynamic Coefficients in Rotordynamics delivers an authoritative guide to the fundamentals of bearing and bearing dynamic coefficients containing various computation methods. Three of the most popular and state-of-the-art methods of determining coefficients are discussed in detail. The computation methods covered include an experimental linear method created by the author, and numerical linear and nonlinear methods using the finite element method. The author—a renowned expert on the topic—presents the results and discusses the limitations of the various methods. Accessibly written, the book provides a clear analysis of the fundamental phenomena in rotor dynamics and includes many illustrations from numerical analysis and the results of the experimental research. Filled with practical examples, the book also includes a companion website hosting code used to calculate the dynamic coefficients of journal bearings. This important book: Covers examples of different computation methods, presents results, and discusses limitations of each Reviews the fundamentals of bearing and bearing dynamic coefficients Includes illustrations from the numerical analysis and results of the experimental research Offers myriad practical examples and a companion website Written for researchers and practitioners working in rotordynamics, Bearing Dynamic Coefficients in Rotordynamics will also earn a place in the libraries of graduate students in mechanical and aerospace engineering who seek a comprehensive treatment of the foundations of this subject.

Download or read book A Comparison of Experimental and Theoretical Results for Leakage Pressure Gradient and Rotordynamic Coefficients for Tapered Annular Gas Seals written by David Alan Elrod and published by . This book was released on 1986 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Comparison of the Theoretical and Experimental Rotordynamic Coefficients for Compressible Flow in a Smooth Annular Seal written by Christopher Hale Connor and published by . This book was released on 1994 with total page 210 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Measurements Versus Predictions for Rotordynamic Coefficients and Leakage Rates for a Novel Hole pattern Gas Seal written by Brent Alan Seifert and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Results are presented for measured and predicted rotordynamic coefficients and leakage for hole-pattern seals with a hole depth that varies axially along the seal. Testing was done to discover how pressure ratio, inlet preswirl, and rotor speed affect the seals' rotordynamic characteristics and leakage. The results were compared to a constant hole depth hole-pattern seal. Experimental results show that the seals' rotordynamic characteristics are not strongly influenced by pressure ratio. There were three preswirl conditions tested, each separated by a 6.9 bar (100psi) difference in inlet pressure. Therefore, normalized preswirl results were compared. The normalized results indicate that introducing inlet fluid preswirl affects the cross coupled stiffness and effective damping coefficients. Inlet preswirl increases the magnitude of cross-coupled stiffness. Effective damping decreases with inlet preswirl, as well as the effective damping cross-over frequency increasing. These results indicate that swirl brakes would be of great value. Rotor speed had a significant effect on the cross-coupled coefficients; both increased with speed. Experimental results were compared to results for a constant hole depth hole pattern seal. The variable hole-depth seal has higher direct damping. The cross-coupled stiffness and cross-coupled damping coefficients were very similar. The direct stiffness was always lower at lower frequencies and higher at higher frequencies for the variable hole depth hole-pattern seal. This was also the case for effective stiffness. The effective damping of the variable hole-depth seal was not only larger than for the constant hole depth seal, it also had a drastically lower cross-over frequency. The difference in cross-over frequency was 40 percent on average. Experimental results for rotordynamic characteristics and leakage were compared to theoretical predictions by ISOTSEAL 2, a modified version of ISOTSEAL. Both cross-coupled stiffness and damping are reasonably predicted. Direct damping is always under-predicted. ISOTSEAL 2 does a poor job of predicting direct stiffness. Direct stiffness is over-predicted at lower frequencies and under-predicted at higherfrequencies. This is also the case for effective stiffness. ISOTSEAL 2 under-predicts the direct damping, but does an excellent job of predicting the direct damping crossover frequency. Seal leakage is well predicted by ISOTSEAL 2.

Download or read book Rotordynamics of Turbomachinery written by John M. Vance and published by John Wiley & Sons. This book was released on 1991-01-16 with total page 404 pages. Available in PDF, EPUB and Kindle. Book excerpt: Describes the rotordynamic considerations that are important to the successful design or troubleshooting of a turbomachine. Shows how bearing design, fluid seals, and rotor geometry affect rotordynamic behavior (vibration, shaft whirling, bearing loads, and critical speeds), and describes two successful computational methods for rotordynamic analysis in terms that can be understood by practicing engineers. Gives descriptive accounts of the state of the art in several areas of the field and presents important mathematical or computational concepts, describing equations and formulas in physical terms for better understanding. Also offers tips for troubleshooting unstable machines and provides practical interpretations of vibration measurements.

Download or read book Monthly Catalogue United States Public Documents written by and published by . This book was released on 1995 with total page 1994 pages. Available in PDF, EPUB and Kindle. Book excerpt: