Numerically generating topology of the liner finish in internal combustion engines

Internal combustion (IC) engines are broadly utilized today. The friction caused by piston rings in IC engines contributes around 20% of the mechanical friction losses. The liner finish is the most critical parameter to define the tension and other design parameters of the piston rings for proper sealing. This work is focused on developing numerical approaches to generating liner finishes based on certain values of topology parameters. The generated surface is able to simulate the lubrication and dry contact behaviors of the original surface, so that the method is used to study the effects of various topology parameters on friction losses. First, methods to analyze, generate, test, and compare honed liner surfaces have been developed. The algorithm to analyze the topology parameters of honed surfaces is described. The honed surfaces are numerically generated and compared with the experimental data. Moreover, the topological variables are changed and the corresponding friction behaviors are studied. The relations between topology variables and friction losses are illustrated. We also developed a quantitative relation between two ISO standards describing the honed liner finish, so that the manufacturing industry can use the surface generation method in convenience. Second, attempts were made to simulate the break-in processes for honed liner finish. Measured and numerically generated surfaces are simulated and compared. The friction and pressure behaviors for lightly and heavily worn surfaces are compared with experimental data. Moreover, by tuning the worn parameters, the friction effective mean pressure (FMEP) curve can match the experimental data. Finally, the algorithm to numerically generate thermally sprayed liner finish is described. The hydrodynamic and dry contact friction behaviors for generated surfaces are compared with experimental data. Critical topology parameters are tuned and their effects on friction losses are studied. Moreover, the effects of the pores created by the plasma spraying processes on the lubrication behaviors are simulated.

Department dc:contributor.department

Massachusetts Institute of Technology. Department of Materials Science and Engineering.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2015

Author dc:creator

• Wang, Renze, S.M. Massachusetts Institute of Technology

Advisor dc:contributor.advisor

• Tian Tian.

• Materials Science and Engineering.
• Mechanical Engineering.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/101853

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/101853