1998-05-04

Rheology of Soot Thickened Diesel Engine Oils 981369

Soot-induced thickening can lead to significant increases in lubricant viscosity in modern diesel engines and forms a major part of diesel engine oil specifications. Despite its importance, relatively little is known about the viscosity characteristics of soot containing oils over conditions relevant to a wide range of engine operating conditions. In this paper, a detailed study of the rheological properties of soot loaded oils from Mack T-8 and Cummins M-11 tests are described. The rheological behaviour is highly complex, particularly as oils become increasingly non-Newtonian in character due to flocculation of soot particles. The role of temperature is critical in the development of flocculated structures, and its effect on viscosity. Extensive soot thickening in oils under moderately quiescent conditions can lead to marked yield stresses at low temperatures (below zero °C). The relative performance of different oils varies across the range of temperatures studied (100 to -25°C). Rotational viscometry offers an improved means of assessment of the ability of a lubricant to control viscosity increase using a self-contained measurement.

SAE MOBILUS

Subscribers can view annotate, and download all of SAE's content. Learn More »

Access SAE MOBILUS »

Members save up to 18% off list price.
Login to see discount.
Special Offer: Download multiple Technical Papers each year? TechSelect is a cost-effective subscription option to select and download 12-100 full-text Technical Papers per year. Find more information here.
We also recommend:
JOURNAL ARTICLE

Crankcase Sampling of PM from a Fired and Motored Compression Ignition Engine

2011-24-0209

View Details

TECHNICAL PAPER

Emission Performance of Lignin-Derived Cyclic Oxygenates in a Heavy-Duty Diesel Engine

2012-01-1056

View Details

JOURNAL ARTICLE

Research on Emissions and Engine Lube Oil Deterioration of Diesel Engines with BioFuels (RME)

2011-01-1302

View Details

X