ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Finite element modeling of contact conditions in multibody system dynamics (1993)
    Springer
    Nonlinear dynamics 4 (1993), S. 83-102 
    Details
    ISSN: 1573-269X
    Keywords: Finite element modeling ; time-variant constraint ; multibody dynamics ; contact analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract In this paper a new method is developed for the dynamic analysis of contact conditions in flexible multibody systems undergoing a rolling type of motion. The relative motion between the two contacting bodies is treated as a constraint condition describing their kinematic and geometric relations. Equations of motion of the system are presented in a matrix form making use of Kane's equations and finite element method. The method developed has been implemented in a general purpose program called DARS and applied to the simulation and analysis of a rotating wheel on a track. Both the bodies are assumed flexible and discretized using a three dimensional 8-noded isoparametric elements. The time variant constraint conditions are imposed on the nodal points located at the peripheral surfaces of the bodies under consideration. The simulation is carried out under two different boundary conditions describing the support of the track. The subsequent constraint forces associated with the generalized coordinates of the system are computed and plotted. The effects of friction are also discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00047122
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    MATHEMATICAL MODEL OF A TIME AND POSITION VARIANT EXTERNAL LOAD ON A GEAR TOOTH USING THE MODIFIED TIMOSHENKO BEAM EQUATION (1996)
    Chichester [u.a.] : Wiley-Blackwell
    International Journal for Numerical Methods in Engineering 39 (1996), S. 2073-2094 
    Details
    ISSN: 0029-5981
    Keywords: singular value decomposition ; finite difference method ; modified Timoshenko equation ; dynamic model ; gear dynamics ; gear tooth testing ; Engineering ; Engineering General
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mathematics , Technology
    Notes: A piece wise continuous closed-form dynamic model of spur gear teeth meshing, using the modified Timoshenko beam equation for a stubby cantilever beam of varying cross-sectional area, is presented. The kinematics and kinetic relationships of a shaft-driven spur gear are used to determine the force on the involute surface of the gear tooth. A convenient set of equations, used to locate this force, is presented. The co-ordinates of this force are given with respect to a gear fixed coordinate system, located at the base of the gear tooth. The governing equations of motion were then numerically solved, and dynamic simulations of the gear tooth response at different gear speeds were performed. This model was then compared with the empirical data from research performed at the NASA Lewis Research Center.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
  • 3
    facet.materialart.
    Unknown
    Performance and Durability of High Temperature Foil Air Bearings for Oil-Free Turbomachinery (2000)
    In:  CASI
    Details
    Publication Date: 2019-07-13
    Description: 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 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, PS304, 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 PS304 coating are well suited for advanced high temperature, oil-free turbomachinery applications.
    Keywords: Aircraft Propulsion and Power
    Type: NASA/TM-2000-209187/REV1 , NAS 1.15:209187/REV1 , ARL-TR-2202 , E-11697-1/REV1 , May 07, 2000 - May 11, 2000; Nashville, TN; United States
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 4
    facet.materialart.
    Unknown
    Performance and Durability of High Temperature Foil Air Bearing for Oil-Free Turbomachinery (1999)
    In:  CASI
    Details
    Publication Date: 2019-07-13
    Description: 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 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, PS304, 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 PS304 coating are well suited for advanced high temperature, oil-free turbomachinery applications.
    Keywords: Aircraft Propulsion and Power
    Type: NASA/TM-1999-209187 , NAS 1.15:209187 , E-11697 , May 07, 2000 - May 11, 2000; Nashville, TN; United States
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...