Search Results

Past oil consumption reduction efforts were motivated by operating cost, petroleum conservation, or customer quality perception concerns. Recent efforts have been driven by exhaust catalyst poisoning considerations. The need to certify emissions to a higher mileage level and optimization efforts on the emission control systems have resulted in higher objectives for oil control. This paper focuses on one important factor in the control of lubrication oil consumption in internal combustion engines. Previous studies have related bore finish to oil consumption through either theoretical or experimental techniques. In this study, a mathematical model is derived statistically from experimental data utilizing regression analysis and a new transient radiotracer oil consumption measurement technique. The model predicts oil consumption levels expected with variations in cylinder bore finish, and suggests the important surface finish parameters to specify and control for minimum oil consumption.

This study was conducted to assess the effects of a low sulfur (<0.05 wt.%) fuel and an uncatalyzed ceramic particle trap on heavy-duty diesel emissions during both steady-state operation and during periods of electrically assisted trap regeneration. A Cummins LTA10-300 engine was operated at two steady-state modes with and without the trap. The exhaust trap system included a Corning EX-54 trap with an electrically assisted regeneration system. Both regulated emissions (oxides of nitrogen - NOx, total hydrocarbons - HC, and total particulate matter - TPM) and some unregulated emissions (polynuclear aromatic hydrocarbons - PAH soluble organic fraction - SOF, sulfates, vapor phase organics, and mutagenic activity) were measured during baseline, trap, and regeneration conditions. Emissions were collected with low sulfur (0.01 wt.%) fuel and compared to emissions with a conventional sulfur (0.32 wt.%) fuel. These fuels also varied in other fuel properties.