Experimental investigation into the effects of diesel dilution on engine lubrication

The dilution of lubricant due to contamination with diesel fuel is an increasingly prevalent, potentially important and poorly understood issue. This study addresses two fundamental questions: 1) How does the change in rheology affect engine lubrication? 2) chemical performance components (base oil additives) impacted by under different lubrication regimes (boundary/full film, hydrodynamic/elastohydrodynamic). achieved testing three samples: neat fully formulated 0W-30 oil, diluted at a concentration 15%, denoted “0W-30D”, 3) neat, fully-formulated 0W-16, same base additives as 0W-30, but blended give viscosity equal that equivalent “0W-30D”. Tribometer tests, including low pressure, shear viscosity, Ultra-high Shear Viscosity (USV), elastohydrodynamic film thickness, 4) Stribeck friction 5) boundary wear, are then conducted. To further emulate conditions, curve measurements performed on lubricants using journal bearing test rig, fitted connecting-rod commercial shells. Results suggest only slightly affects additive (with modifiers being more inhibited than anti-wear reduce both thickness. However, care must be taken viscometrics predict behaviour because pressure coefficient also affected which has implications for elastohydrodynamically contacts, thinning means modifier effects lose their functions high rates; whereas throughout whole rate range. • characterization regimes. Comparison between undiluted real bearings. Assessment rheology. friction-modifier, additives.