Technical Reports

Users' Manual for Kalker's Simplified Nonlinear Creep Theory

  • 01
  • Dec
  • 1977
AUTHOR: James G. Goree, E. Harry Law
OFFICE: RPD
REPORT NUMBER: FRA/ORD-78/06
SUBJECT: Evaluation
KEYWORDS: Creepage, Creep Forces, Spin Moment, Steady-State Rolling, Hertz Contact
ABSTRACT: The conversion of the computer program, "Simplified Theory of Rolling Contact," (used for calculation of a nonlinear creep force-creepage relationship) from the original Algol language to Fortran is considered. The Algol program was written by Professor J. J. Kalker and was derived from the paper, "Simplified Theory of Rolling Contact," Delft Progr. Rep., Series C: Mechanical and. Aeronautical Engineering and Shipbuilding, 1 (1973), pp. 1-10. A significant number of changes was made in the program for more convenient use; however, the fundamental equations remain unchanged. The results were checked in detail to insure agreement with the original solution. The program gives an appropriate solution for the resultant tangential creep forces and spin moment acting between two bodies of equal linearly elastic material properties. The creep forces and spin moment are due to lateral, longitudinal, and spin creepages. Assumptions corresponding to the Hertz contact theory are implied and two additional simplifying assumptions are made, resulting in a significant reduction in computation time as contrasted with previous solutions. Two separate computer codes were developed, the first being the general solution with extended input and output, and the second a shortened version primarily intended for use as a subroutine. Surprisingly good agreement is found to exist between the "Simplified Theory" and published experimental results for a wide range of contact ellipse eccentricity.

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