Frictional Characteristics of Ultrasonically Measured Lubricant Films in a Simulated Piston Ring Liner Contact
Published April 12, 2011 by SAE International in United States
Annotation of this paper is available
An essential part of the total parasitic loss in an IC engine is due to the piston ring and liner friction. In this work, a piston ring-liner reciprocating test rig combined with ultrasonic film thickness measurement system was used to understand frictional characteristic of the lubricant that formed in the contact. Two test procedures were carried out for two lubricants with different viscosities. These procedures were a step load increment at a constant speed and a step speed increment at a constant load. The results showed that the piston ring-liner contact was in boundary lubrication regime for low operating speeds at high load. This was consistent with the oil film thickness data. However, mixed lubrication regime was observed for high operating speeds at low loads. The lubricant film thicknesses increased with speed and decreased with load. The correlation between friction and film thickness showed both the transitions in lubrication regime and the effect of viscosity and lubricant additive package. The experimental method is a first stage towards the measurement of oil films in a fired automotive engine.
CitationAvan, E., Mills, R., and Dwyer-Joyce, R., "Frictional Characteristics of Ultrasonically Measured Lubricant Films in a Simulated Piston Ring Liner Contact," SAE Technical Paper 2011-01-1400, 2011, https://doi.org/10.4271/2011-01-1400.
- Andersson, B.S., “Company Perspectives in Vehicle Tribology-Volvo,” 17th Leeds-Lyon Symposium on Tribology-Vehicle Tribology, Tribology series, 18:503-506, 1991.
- Ting, L., “Development of a Reciprocating Test Rig for Tribological Studies of Piston Engine Moving Components - Part II: Measurements of Piston Ring Friction Coefficients and Rig Test Confirmation,” SAE Technical Paper 930686, 1993, doi: 10.4271/930686.
- Akalın, O., and Newaz, G.M., “Piston Ring-Cylinder Bore Friction Modelling in Mixed Lubrication Regime: Part II- Correlation with Bench Test Data,” Journal of Tribology, 123:219-223, 2001.
- Bolander, N.W., Steenwyk, B.D., Sadeghi, F., and Gerber, G.R., “Lubrication Regime Transitions at the Piston Ring-Cylinder Liner Interface,” Proc. IMechE Part J: Journal of Engineering Tribology 219:19-31, 2005.
- Dearlove, J. and Cheng, W., “Simultaneous Piston Ring Friction and Oil Film Thickness Measurements in a Reciprocating Test Rig,” SAE Technical Paper 952470, 1995, doi: 10.4271/952470.
- Truhan, J.J. Qu, J, and Blau, P.J., “A Rig Test to Measure Friction and Wear of Heavy Duty Diesel Engine Piston Rings and Cylinder Liners using Realistic Lubricants,” Tribology International 38:211-218, 2005.
- Hartfield-Wünsch, S., Tung, S., and Rivard, C., “Development of a Bench Wear Test for the Evaluation of Engine Cylinder Components and the Correlation with Engine Test Results,” SAE Technical Paper 932693, 1993, doi: 10.4271/932693.
- Avan, E., Mills, R., and Dwyer-Joyce, R., “Ultrasonic Imaging of the Piston Ring Oil Film During Operation in a Motored Engine - Towards Oil Film Thickness Measurement,” SAE Int. J. Fuels Lubr. 3(2):786-793, 2010, doi:10.4271/2010-01-2179.
- Dwyer-Joyce, R.S., Drinkwater, B.W., and Donohoe, C.J., “The measurement of lubricant-film thickness using ultrasound,” Proc. Royal Society, 459:957-958, 2003.
- Stochowiak, G.W., and Batchelor, A.W., “Engineering Tribology,” Elsevier Butterworth Heinemann, USA. 2005.