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High Cycle Fatigue: A Mechanics of Materials Perspective part 58

High Cycle Fatigue: A Mechanics of Materials Perspective part 58. The nomenclature used in this book may differ somewhat from what is considered standard or common usage. In such instances, this has been noted in a footnote. Additionally, units of measurement are not standard in many cases. While technical publications typically adhere to SI units these days, much of the work published by the engine manufacturers in the United States is presented using English units (pounds, inches, for example), because these are the units used as standard practice in that industry. The graphs and calculations came in those units and no attempt was made to convert. | 556 Appendix F Figure F.5. Ratio of peak pressure Praax to peak pressure P0max for increasing thickness to contact length ratio for two pad geometries. the correct contact length a stick zone size c pressure eccentricity e stick zone eccentricity ec the normal rigid-body displacement 3v the tangential rigid body displacement 3u and the pad profile rotation angle 0m . The peak pressure Pmax was also calculated for increasing specimen thickness to study the thickness effect on the pressure distribution. A normal load of 1.2 x 106N m was applied to a pad geometry of 51 mm radius pad as well as a 3-mm flat and edge radius pad for increasing thickness. The peak pressure was obtained for each specimen thickness and pad geometry and normalized with the peak pressure P0 max obtained from the half-space solution. Figure F.5 shows that the CARTEL solution finite thickness approaches the CAPRI solution half-space for a thickness where the thickness to contact length ratio b a is greater than 5. The half-contact length that was used for the two pad geometries was a 1.1 mm for the cylindrical pad and a 1.7 mm for the flat pad. REFERENCES 1. Hills D.A. Nowell D. and Sackfield A. Mechanics of Elastic Contacts Kluwer Academic Publishers 1992. 2. Murthy H. Harish G. and Farris T.N. Efficient Modeling of Fretting of Blade Disk Contacts Including Load History Effects ASME Journal of Tribology 126 2004 pp. 56-64. 3. Ciavarella M. Hills D.A. and Monno G. The Influence of Rounded Edges on Indentation by a Flat Punch Proc. Inst. Mech. Eng. Part C J. Mech. Eng. Sci. 212 4 1998 pp. 319-328. 4. Jager J. Half-planes Without Coupling Under Contact Loading Archive of Applied Mechanics 67 1997 pp. 247-259. 5. Goryacheva I.G. Murthy H. and Farris T.N. Contact Problem with Partial Slip for the Inclined Punch with Rounded Edges Int. J. Fatigue 24 2002 pp. 1191-1201. Appendix F 557 6. Barber J.R. Elasticity Kluwer Academic Publishers Netherlands 1992. 7. Mindlin R.D. Compliance of Elastic Bodies in