This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
ANALYSIS OF TRANSIENT MINIMUM FILM THICKNESS IN CAM AND FLAT FOLLOWER
Technical Paper
2000-05-0163
Annotation ability available
Sector:
Event:
Language:
English
Abstract
In order to verify the characteristics of frictional resistance and wear in valve train components, it is the basic investigation to find the minimum film thickness of contacting components. This verification gives useful clue for better performance and endurance life of the whole engine system. The applied loads and the relative contacting velocities during the cycle are obtained from the simulation of kinematics and dynamics of push-rod type valve train system. The contact geometry between cam and follower is very non-conformal that results in concentrated fluid film pressure and very high-stress on the contact region. Both loads of high fluctuation and relative sliding velocities of sudden change in cam and follower contact frequently make it impossible to get both converged and stable solutions with conventional numerical method. Multigird multi-level method for the solver of non-linear partial differential equation including solid deformation is used in our study for the numerical convergence and stability. With this numerical algorithm, the minimum film thickness under dynamic loading condition is computed and compared to that of steady loading condition and Dowson-Hamrock curve fitting formula. In our work, we developed computation tools both for kinematics and dynamics of valve train system of push-rod type and for fluid film thickness with elastic deformation on the basis of dynamic loading condition with multigrid multilevel method.
Recommended Content
| Technical Paper | Modeling, Validation and Dynamic Analysis of Diesel Pushrod Overhead Bridged Valve Train |
| Journal Article | Simulation of a Valve Train Using Non-Smooth Mechanics |
| Technical Paper | Computer-Assisted Valve Train Design and Development |
Authors
Citation
Jang, S., "ANALYSIS OF TRANSIENT MINIMUM FILM THICKNESS IN CAM AND FLAT FOLLOWER," SAE Technical Paper 2000-05-0163, 2000.Also In
References
- Goenka, P. K. Paranipe, R. S. Jeng, Y.-R. “FLARE: An Integrated Package for Friction and Lubrication Analysis of Automotive Engines,” SAE 92047
- Dyson, A. 1980 “Kinematics and Geometry of Cam and Finger Follower System,” Tribology Int. 13 3 121 132
- Lee, J. Patterson, D. J. 1997 “Nonlinear Valve Train Dynamics Simulation with a Distributed Parameter Model of Valve Springs,” Journal of Engineering for Gas Turbines and Power 119 692 698
- Paranjpe, R. S. Gecim, B. A. “Comparative Friction Assessment of Different Valve-Train Types Using the FLARE Code,” SAE 920491
- Paranjpe, R. S. 1990 “Dynamic Analysis of a Valve Spring with a Coulomb-Friction Damper,” Journal of Mechanical Design 112 509 513
- Houpert, L. Hamrock, B. J. 1986 “Fast Approach for Calculating Film Thickness and Pressures in Elastohydrodynamically Lubricated Contacts at High Loads,” Journal of Tribology 108 411 420
- Dowson, D. Taylor, C. M. Zhu, G. 1992 “A Transient Elastohydrodynamic Lubrication Analysis of a Cam and Follower,” Journal of Physics: Applied Physics 25 A-313 A320
- Dowson, D. Harrison, P. Taylor, C. M. 1985 “The Lubrication of Automotive Cams and Followers,” Mechanism and Surface Distress, 12 th Leeds-Lyon Conference 305 322
- Scales, L.E. Rycroft, J. E. Horswill, N. R. Williamson, B. P. “Simulation and Observation of Transient Effects in Elastohydrodynamic Lubrication,” SAE 961143
- Lubrecht, A. Napel W. E. ten Bosma, R. 1986 “Multigrid, An Alternative Method for Calculating Film Thickness and Pressure Profiles in Elastohydrodynamically Lubricated Line Contacts,” Journal of Tribology 108 551 556
- Hanachi, S. Freudenstein, F. 1986 “The Development of a Predictive Model for the Optimization of High-Speed Cam-Follower Systems with Coulomb Damping Internal Friction and Elastic and Fluidic Elements,” Journal of Mechanisms, Transmissions, and Automation in Design 108 506 515
- Matthews, J. Sadeghi, F. 1996 “Kinematics and Lubrication of Camshaft Roller Follower Mechanics,” Tribology Transactions 39 425 433
- Stone, R. Leornard, H. J. 1994 “Determination of the Instaneous Radius of Curvature of a Cam at the Contact Point with a flat Follower Moving Othorgonally,” Journal of Engineering Tribology 208 147 149
- Taylor, C. M. 1993 Engine Tribology Elsevier