Feasibility of observing small differences in friction mean effective pressure between different lubricating oil formations using small, single-cylinder motored engine rig

Journal Article · Tue Sep 01 00:00:00 EDT 2015 · Tribology Transactions

DOI:https://doi.org/10.1080/10402004.2015.1041627· OSTI ID:1213983

Rohr, William F. ^[1]; Nguyen, Ke ^[1]; Bunting, Bruce G. ^[2]; Qu, Jun ^[2]

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1. Univ. of Tennessee, Knoxville, TN (United States)
2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Here, the feasibility of using a motored single-cylinder 517 cc diesel engine to observe small frictional differences between oil formulations is investigated. Friction mean effective pressure (FMEP) is measured and compared for an SAE 10W-30 and an SAE 5W-20 oil in three stages of production: base oil, commercial oil without a friction and wear reducing additive, and fully formulated commercial oil. In addition, a commercial SAE 5W-30 engine oil is investigated. Friction mean effective pressure is plotted versus oil dynamic viscosity to compare the lubricant FMEP at a given viscosity. Linear regressions and average friction mean effective pressure are used as a secondary means of comparing FMEP for the various oil formulations. Differences between the oils are observed with the base oil having higher friction at a given viscosity but a lower average FMEP due to the temperature distribution of the test and lower viscosities reached by the base oil. The commercial oil is shown to have both a higher FMEP at a given viscosity and a higher average FMEP than the commercial oil without a friction and wear reducing additive. The increase in friction for the oil without a friction and wear reduction additive indicates that the operational regime of the engine may be out of the bounds of the optimal regime for the additive or that the additive is more optimized for wear reduction. Results show that it is feasible to observe small differences in FMEP between lubricating oil formulations using a small, single-cylinder motored engine.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE)
• Grant/Contract Number: AC05-00OR22725
• OSTI ID: 1213983
• Journal Information: Tribology Transactions, Vol. 58, Issue 6; ISSN 1040-2004
• Publisher: Taylor & Francis
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
42 ENGINEERING
friction test methods
diesel engine oils
diesel engines
FMEP
automotive