The effect of surface finish on piston ring-pack performance in advanced reciprocating engine systems

Frictional losses in the piston ring-pack of an engine account for approximately 20% of the total frictional losses within an engine. Methods of surface texture optimization were investigated to reduce piston ring-pack friction and increase engine brake thermal efficiency. Adverse effects of surface texture optimization on engine oil consumption and durability were also considered. Although many non-conventional cylinder liner finishes are now being developed to reduce friction and oil consumption, the effects of surface finish on ring-pack performance is not well understood. To enable the study of cylinder liner surface texture on predicted piston ring-pack performance, the description of surface texture in MIT's current ring-pack models was improved. Modifications were made to the asperity contact and oil flow resistance sub-models to enable a more accurate and more general description of surface texture. The accuracy of the new sub- models was validated with experimental results obtained from a ring reciprocating tester. With the use of these sub-models, ring pack friction reduction strategies were investigated. The effects of surface skewness, roughness, and honing cross-hatch angle were considered in detail. The analytical results suggest that a negatively skewed surface finish, such as that produced by plateau honing, will lead to a ring-pack friction reduction relative to a conventionally honed surface. This predicted friction reduction was due to a decrease in rough surface asperity contact between the rings and liner. Additional friction reduction was predicted by decreasing the honing cross hatch angle.

Department dc:contributor.department

Massachusetts Institute of Technology. Department of Mechanical Engineering

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2005

Author dc:creator

• Jocsak, Jeffrey (Jeffrey Alan)

Advisor dc:contributor.advisor

• Tian Tian and Victor W. Wong.

• 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/1721.1/32371

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/32371