0
TECHNICAL PAPERS

Modeling of Film Thickness and Traction in a Variable Ratio Traction Drive Rig

[+] Author and Article Information
K. J. Sharif, H. P. Evans, R. W. Snidle

School of Engineering, Cardiff University, Cardiff, U.K.

J. P. Newall

Torotrak (Development) Ltd., Leyland, U.K.

J. Tribol 126(1), 92-104 (Jan 13, 2004) (13 pages) doi:10.1115/1.1609490 History: Received February 12, 2003; Revised June 26, 2003; Online January 13, 2004
Copyright © 2004 by ASME
Your Session has timed out. Please sign back in to continue.

References

Heumann, H., Briffet, G., Burke, M., Field, M., Fuller, J., Lee, A. P., and Newall, J. P., 2002, “System Efficiency Optimization of the Torotrak Infinitely Variable Transmission (IVT),”CVT 2002 Congress, VDI, Munich, October 2002.
Dyson,  A., 1970, “Frictional Traction and Lubricant Rheology in Elastohydrodynamic lubrication,” Philos. Trans. R. Soc. London, A266, pp. 1–33.
Hirst,  W., and Moore,  A. J., 1974, “Non-Newtonian Behavior in Elastohydrodynamic Lubrication,” Proc. R. Soc. London, Ser. A, 337, pp. 101–121.
Johnson,  K. L., and Tevaarwerk,  J. L., 1977, “The Shear Behavior of Elastohydrodynamic Oil Films,” Proc. R. Soc. London, Ser. A, 356, pp. 215–236.
Conry,  T. F., Wang,  S., and Cusano,  C., 1987, “A Reynolds-Eyring Equation for Elastohydro-Dynamic Lubrication in Line Contacts,” ASME J. Tribol., 109, pp. 648–654.
Kim,  K. H., and Sadeghi,  F., 1991, “Non-Newtonian Elastohydro-Dynamic Lubrication of Point Contact,” ASME J. Tribol., 113, pp. 703–711.
Sharif,  K. J., Kong,  S., Evans,  H. P., and Snidle,  R. W., 2001, “Contact and Elastohydrodynamic Analysis of Worm Gears: Part 1 Theoretical Formulation,” Proc. Inst. Mech. Eng., Part C: J. Mech. Eng. Sci., 215, pp. 817–830.
Bair,  S., and Winer,  W. O., 1979, “A Rheological Model for Elastohydrodynamic Contacts Based on Primary Laboratory Data,” ASME J. Lubr. Technol., 101, pp. 258–265.
Bair, S., and Winer, W. O., 2000, “The Pressure-Viscosity Coefficient at Hertz Pressure and Its Relation to Concentrated Contact Traction,” Proc. 26th Leeds-Lyon Symp. on Tribology, Elsevier, Amsterdam pp. 433–443.
Newall, J. P., Nicolson, D. M., Lee, A. P., and Evans, S. P., 2002, “Development and Assessment of Traction Fluids for Use in Toroidal (IVT) Transmissions,” SAE 2002 World Congress, Transmissions and Drive-lines Symposium, March 2002.
Plint,  M. A., 1967, “Traction in Elastohydrodynamic Contacts,” Proc. I. Mech. E., 182, n14, pp. 300–306.
Holmes,  M. J. A., Evans,  H. P., Hughes,  T. G., and Snidle,  R. W., 2003, “Transient Elastohydrodynamic Point Contact Analysis Using a New Coupled Differential Deflection Method: Part 1 Theory and Validation,” Proc. Inst. Mech. Eng., Part J: J. Eng. Tribol. 217, pp. 289–303.
Evans,  H. P., and Hughes,  T. G., 2000, “Evaluation of Deflection in Semi-Infinite Bodies by a Differential Method,” Proc. Inst. Mech. Eng., Part C: J. Mech. Eng. Sci., 214, pp. 563–584.
Larsson,  R., Larsson,  P. O., Eriksson,  E., Sjöberg,  M., and Höglund,  E., 2001,“Lubricant Properties for Input to Hydrodynamic and Elastohydro-Dynamic Lubrication Analyses,” Proc. Inst. Mech. Eng., Part J: J. Eng. Tribol., 201, pp. 17–28.
Yasutomi,  S., Bair,  S., and Winer,  W., 1984, “An Application of a Free Volume Model to Lubricant Rheology,” ASME J. Tribol., 106, pp. 291–303.
Evans,  C. R., and Johnson,  K. L., 1986, “The Rheological Properties of Elastohydrodynamic Lubricants,” Proc. Inst. Mech. Eng., Part C: Mech. Eng. Sci., 200, pp. 303–312.
Johnson, K. L., 1993, “Non-Newtonian Effects in Elastohydro-Dynamic Lubrication,” Thin Films in Tribology, Proc. 19th Leeds-Lyon Symposium, Elsevier, Amsterdam, pp. 25–26.
Fang,  N., Chang,  L., Johnson,  G. J., Webster,  M. N., and Jackson,  A., 2001, “An Experimental/Theoretical Approach to Modelling the Viscous Behavior of Liquid Lubricants in Elastohydrodynamic Lubrication Contacts,” Proc. Inst. Mech. Eng., Part J: J. Eng. Tribol., 215, pp. 311–319.

Figures

Grahic Jump Location
Test head arrangement of the Torotrak traction rig with contact between spherical rollers of radius R rotating about axes AA and CC, and plane disks, at a track radius Rt, rotating about axis BB
Grahic Jump Location
Processed data from traction test (♦ clockwise rotation, • anticlockwise rotation) of top shaft
Grahic Jump Location
Variation of test track thermocouple temperature for the tests at 60°C: ○ u⁁=4 m/s, × u⁁=11 m/s, □ u⁁=18 m/s
Grahic Jump Location
Yasutomi viscosity formula for Santotrac 50 16 for temperatures of 50, 70, 100, 140, 180, 200, and 220°C
Grahic Jump Location
Traction curves obtained using an Eyring model for the 90°C, 11 m/s experiments. Viscosity Model I upper curves, Model II lower curves, symbols show experiments. Solid curves and ♦, Rt=30 mm; broken curves and ⋄, Rt=47 mm.
Grahic Jump Location
Traction curves at two temperatures with 11 m/s entrainment velocity using τ0=A and τ0=Bp established from low slip behavior; ♦ experiment, □ τ0=A, ○ τ0=Bp
Grahic Jump Location
Variation of constants A and B with nominal temperature of experiment
Grahic Jump Location
Traction curves for T=60°C,u⁁=18 m/s; ⋄ τ0=Aq(T),+τ0=Bp q(T), □ τ0=A, × τ0=Bp, ♦ experiment
Grahic Jump Location
Least square best fit models compared with experiment for 30 mm track radius experiments. ♦ experiment, □ Eyring model, ○ limiting shear stress model, ▵ combined model, × points used for least square fit. Traction curves are arranged by column for entrainment speed and by row for experiment nominal temperature.
Grahic Jump Location
Least square best fit models based on fits to the 90°C and 120°C experiments compared with experimental results. ♦ experiment, □ Eyring model, ○ limiting shear stress model, × points used for least square fit. Traction curves are arranged by column for entrainment speed and by row for experiment nominal temperature.
Grahic Jump Location
Contours of (a) pressure/MPa, and (b) film thickness/μm for the case u⁁=11 m/s,θref=90°C,ξ=0.01. Broken circle indicates Hertzian contact area.
Grahic Jump Location
Contours of temperature/°C for the case u⁁=11 m/s,θref=90°C,ξ=0.01 with Eyring best fit model: (a) sphere surface temperature, (b) disk surface temperature, and (c) mid plane film temperature. Broken circle indicates Hertzian contact area.
Grahic Jump Location
Contours of temperature/°C for the case u⁁=11 m/s,θref=90°C,ξ=0.1 with Eyring best fit model: (a) sphere surface temperature, (b) disk surface temperature, and (c) mid-plane film temperature. Broken circle indicates Hertzian contact area.
Grahic Jump Location
Contours of temperature/°C for the case u⁁=11 m/s,θref=90°C,ξ=0.1 with limiting shear stress best fit model: (a) sphere surface temperature, (b) disk surface temperature, and (c) mid plane film temperature. Broken circle indicates Hertzian contact area.

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In