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Discretization

Discretization. Figure 19.1 Example of dividing area in and around contact zone into equal rectangular areas. [ From Hamrock and Dowson (1976a). ]. Film Profile. Where. Figure 19.2 Components of film thickness for elliptical solid near plane. [From Hamrock and Dowson (1981).].

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Discretization

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  1. Discretization Figure 19.1 Example of dividing area in and around contact zone into equal rectangular areas. [From Hamrock and Dowson (1976a).]

  2. Film Profile Where Figure 19.2 Components of film thickness for elliptical solid near plane. [From Hamrock and Dowson (1981).]

  3. Hard EHL Minimum Film Thickness

  4. Hard EHL Results Figure 19.3 Contour plot of dimensionless pressure with ellipticity parameter k = 1.25 and dimensionless speed, load, and materials parameters held fixed at U = 0.168 x 10-11, W=0.111 x 10-6, and G = 4522. [From Hamrock and Dowson (1977a).] Figure 19.4 Contour plot of dimensionless film thickness with ellipticity parameter k = 1.25 and dimensionless speed, load, and materials parameters held fixed at U = 0.168 x 10-11, W=0.111 x 10-6, and G = 4522. [From Hamrock and Dowson (1977a).]

  5. Comparison of Theory & Experiment Figure 19.5 Theoretical and experimental central and minimum film thickness for pure sliding for two dimensionless load parameters W. (a) W = 0.1238 x 10-6; (b) W = 0.9287 10-6. [From Kunz and Winer (1977).]

  6. Film Thickness

  7. Experimental Verification Figure 19.6 Effect of velocity on central film thickness at constant load (2.6 N) for mineral oil and water-glycol lubricants of similar viscosity. [From Dalmaz and Godet (1978).] Figure 19.7 Predicted dimensionless minimum film thickness from Hamrock and Dowson (1977a) [Eq. (19.16)] compared with experimental results obtained by Koye and Winer. [From Koye and Winer (1980).]

  8. Experimental Verification (cont.) Figure 19.8 Side-leakage factor for elliptical conjunctions in hard EHL. [From Hamrock and Dowson (1981).] Figure 19.9 Effect of ellipticity parameter on ratio of dimensionless minimum film thickness to line-contact dimensionless minimum film thickness, for EHL high- and low-elastic modulus analyses. [From Hamrock and Dowson (1978).]

  9. Film Thickness in Soft EHL

  10. Computing Area Figure 19.10 Computing area in and around Hertzian contact zone. [From Hamrock and Dowson (1977b).]

  11. Starvation Effects

  12. Starvation Effects

  13. Starvation Results - Pressure Figure 19.11 Contour plots of dimensionless pressure for dimensionless inlet distances m of (a) 4, (b) 2, and (c) 1.25 and for group 1 of Table 19.5. [From Hamrock and Dowson (1977b).]

  14. Starvation Results - Film Thickness Figure 19.11 Contour plots of dimensionless film thickness for dimensionless inlet distances m of (a) 4, (b) 2, and (c) 1.25 and for group 1 of Table 19.5. [From Hamrock and Dowson (1977b).]

  15. Starvation for Soft EHL

  16. Starvation Results - Pressure Figure 19.13 Contour plots of dimensionless pressure for dimensionless inlet distances m of (a) 1.967, (b) 1.333, and (c) 1.033 and for group 3 of Table 19.7. [From Hamrock and Dowson (1979a).]

  17. Starvation Results - Film Thickness Figure 19.13 Contour plots of dimensionless film thickness for dimensionless inlet distances m of (a) 1.967, (b) 1.333, and (c) 1.033 and for group 3 of Table 19.7. [From Hamrock and Dowson (1979a).]

  18. Geometry Effects Figure 20.1 Comparison of geometry effects in four lubrication regimes. [From Jeng et al. (1987).]

  19. Lubrication Regimes Figure 20.2 Maps of lubrication regimes for four values of ellipticity parameter k. (a) k=1/2; (b) k=1. [From Esfahanian and Hamrock (1991).]

  20. Lubrication Regimes (cont.) Figure 20.2 Concluded. (c) k=3; (d) k=6.

  21. Temperature along Centerline Figure 20.3 Lubricant and ball surface temperatures along contact centerline. Sliding speed, 1.40 m/s; load 67 N. [From Winer (1983).]

  22. Surface Roughness Effects Figure 20.5 Effect of surface roughness on average film thickness of EHL contacts. [From Zhu and Cheng (1988).]

  23. Roughness Effects on Pressure

  24. Radial Ball Bearings Table 21.1 Characteristics of representative radial ball bearings. [From Hamrock and Anderson (1983).]

  25. Angular-Contact Ball Bearings Table 21.2 Characteristics of representative angular-contact ball bearings (Minimum bore size, 10 mm). [From Hamrock and Anderson (1983).]

  26. Thrust Ball Bearings Table 21.3 Characteristics of representative thrust ball bearings (Relative radial capacity, 0). [From Hamrock and Anderson (1983).]

  27. Cylindrical Roller Bearings Table 21.1 Characteristics of representative cylindrical roller bearings. [From Hamrock and Anderson (1983).]

  28. Spherical Roller Bearings Table 21.5 Characteristics of representative spherical roller bearings. [From Hamrock and Anderson (1983).]

  29. Double Row Spherical Roller Bearings Table 21.6 Characteristics of standardized double row, spherical roller bearings. [From Hamrock and Anderson (1983).]

  30. Spherical Roller Bearings Table 21.7 Characteristics of spherical roller bearings. [From Hamrock and Anderson (1983).]

  31. Tapered Roller Bearings Table 21.8 Characteristics of representative tapered-roller bearings. [From Hamrock and Anderson (1983).]

  32. Needle Roller Bearings

  33. Radial Ball Bearings Figure 21.1 Cross section through radial single-row ball bearings. [From Hamrock and Anderson (1983).] Figure 21.2 Cross section of ball and outer race, showing race conformity. [From Hamrock and Anderson (1983).]

  34. Contact Angle and Endplay Figure 21.3 Cross section of radial bearing, showing ball-race contact due to axial shift of inner and outer races. (a) Initial position; (b) shifted position. [From Hamrock and Anderson (1983).] Figure 21.4 Free contact angle and endplay as a function of cd/2d for four values of total conformity. [From Hamrock and Anderson (1983).]

  35. Ball Bearing Geometry Figure 21.5 Shoulder height in ball bearing. [From Hamrock and Anderson (1983).] Figure 21.6 Cross section of ball bearing. [From Hamrock and Anderson (1983).]

  36. Crowned Bearings Figure 21.7 (a) Spherical roller (fully crowned) and (b) cylindrical roller (partially crowned). [From Hamrock and Anderson (1983).]

  37. Spherical Roller Bearing Figure 21.9 Schematic diagram of spherical roller bearing, showing diametral play and end-play. [From Hamrock and Anderson (1983).] Figure 21.8 Geometry of spherical roller bearing. [From Hamrock and Anderson (1983).]

  38. Contact Angle and Velocity Figure 21.10 Contact angles in ball bearing at appreciable speeds. [From Hamrock and Anderson (1983).] Figure 21.11 Angular velocities of ball. [From Hamrock and Anderson (1983).]

  39. Ball-Spin Axes Figure 21.12 Ball spin axis orientations for (a) outer- and (b) inner-race control. [From Hamrock and Anderson (1983).]

  40. Tapered Roller Bearing Figure 21.13 Simplified geometry for tapered-roller bearing. [From Hamrock and Anderson (1983).]

  41. Radially Loaded Rolling Element Bearing Figure 21.14 Radially loaded rolling-element bearing. (a) Concentric arrangement; (b) initial contact; (c) interference. [From Hamrock and Anderson (1983).]

  42. Contact and Load Figure 21.15 Contact ellipse in bearing race under load. [From Hamrock and Anderson (1983).] Figure 21.16 Angular-contact ball bearing under thrust load. [From Hamrock and Anderson (1983).]

  43. Back-to-Back Arrangement Figure 21.17 Angular-contact bearings in back-to-back arrangement, shown (a) individually as manufactured and (b) as mounted with preload. [From Hamrock and Anderson (1983).]

  44. Load-Deflection Figure 21.18 Thrust load - axial deflection curve for typical ball bearing. [From Hamrock and Anderson (1983).]

  45. Load and Slip in Contact Ellipse Figure 21.19 Differential slip due to curvature of contact ellipse. [From Hamrock and Anderson (1983).] Figure 21.20 Load components in contact ellipse. [From Hamrock and Anderson (1983).]

  46. Friction Figure 21.21 Frictional resistance of ball in conforming groove. [From Hamrock and Anderson (1983).]

  47. Jet Lubrication Figure 21.22 Effectiveness of proper jet lubrication. Test bearings; 20-mm-bore, angular contact ball bearings; thrust load, 222 N (50 lbf). [From Matt and Gianotti (1966).] Figure 21.23 Placement of jets for ball bearings with relieved rings and tapered-roller bearings. [From Parker (1980).]

  48. Underrace Oiling System Figure 21.24 Underrace oiling system for main shaft bearings on turbofan engine. (a) Cylindrical roller bearing; (b) ball thrust bearing. [From Brown (1970).]

  49. Fatigue Spall Figure 21.25 Typical fatigue spall. [From Hamrock and Anderson (1983).]

  50. Bearing Failure Figure 21.26 Distribution of bearing fatigue failures. [From Hamrock and Anderson (1983).] Figure 21.27 Typical Weibull plot of bearing fatigue failures. [From Hamrock and Anderson (1983).]

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