Lubricating Oil Compositions Research Articles

Ignition of Various Lubricating Oil Compositions Using a Shock Tube

Abstract With new restrictions imposed on gas turbine efficiencies and power outputs, lubricating oils are used at higher temperatures and harsher conditions leading to potential, unintended combustion. To establish an understanding of lubricating oil's resistance to combustion, a new spray injector system was utilized in the High-Pressure Shock Tube (HPST) Facility at the TEES Turbomachinery Laboratory at Texas A&M University. Two gas turbine oils (Mobil DTE 732 and Castrol Perfecto X32), a base mineral oil, and a surrogate (n-hexadecane) were tested at postreflected shock conditions at equivalence ratios near 2.5. Castrol Perfecto X32 was also characterized at an equivalence ratio near 1.2. All of the lubricating oils displayed ignition between temperatures of 1152 and 1383 K and near atmospheric pressures. To characterize combustion, two different definitions of ignition delay time (IDT) were considered: sidewall OH* chemiluminescence and sidewall pressure. Both definitions were used to create temperature-dependent correlations for each of the lubricating oils. In general, both definitions provided similar results within the accuracy of the measurements. One trend from the data herein is that the brand-name oils (Mobil DTE 732 and Castrol Perfecto X32) provided ignition delay times that were similar to each other but slightly larger than the corresponding mineral oil and n-hexadecane results. This difference could be attributed to the additives that are present in the brand-name oils.

The effect of diesel fuel sulphur and vanadium on engine performance and emissions

Metallic composition of diesel particulate matter, even though a relatively small proportion of total mass, can reveal important information regarding engine conditions, fuel/lubricating oil characteristics and for health impacts. In this study, a detailed investigation into the metallic elemental composition at different particle diameter sizes has been undertaken. A bivariate statistical analysis was performed in order to investigate the correlation between the metallic element, measured engine performance and engine emission variables. Major sources of metallic elements in the emitted particles are considered in this study, including the fuel and lubricating oil compositions, engine wear emissions and metal-containing dust in the ambient air. Metallic solid ultrafine-particles (Dp < 100 nm) are strongly associated with metallic compounds derived from lubricating oil (Ca, Zn, Mg and K), while the fuel related metallic compounds and engine wear emissions are represented in the accumulation mode particle fraction (>100 nm). Calculated correlation matrices show a clear effect of engine load conditions and fuel S contents on particle number and mass emissions.

A comparative study of the elemental composition of the exhaust emissions of cars powered by liquefied petroleum gas and unleaded petrol

Elements emitted from the exhausts of new Ford Falcon Forte cars powered by unleaded petrol (ULP) and liquefied petroleum gas (LPG) were measured on a chassis dynamometer. The measurements were carried out in February, June and August 2001, and at two steady state driving conditions (60 and 80 km h −1). Thirty seven elements were quantified in the exhaust samples by inductively coupled plasma mass spectrometry (ICPMS). The total emission factors of the elements from the exhausts of ULP cars were higher than those of LPG cars at both engine speeds even though high variability in the exhaust emissions from different cars was noted. The effect of the operating conditions such as mileage of the cars, engine speed, fuel and lubricating oil compositions on the emissions was studied. To investigate the effects of these conditions, multivariate data analysis methods were employed including exploratory principal component analysis (PCA), and the multi-criteria decision making methods (MCDM), preference ranking organization method for enrichment evaluation (PROMETHEE) and geometrical analysis for interactive aid (GAIA), for ranking the cars on the basis of the emission factors of the elements. PCA biplot of the complete data matrix showed a clear discrimination of the February, June and August emission test results. In addition, (i) platinum group elements (PGE) emissions were separated from each other in the three different clusters viz. Pt with February, Pd with June and Rh with August; (ii) the motor oil related elements, Zn and P, were particularly associated with the June and August tests (these vectors were also grouped with V, Al and Cu); and (iii) highest emissions of most major elements were associated with the August test after the cars have recorded their highest mileage. Extensive analysis with the aid of the MCDM ranking methods demonstrated clearly that cars powered by LPG outperform those powered by ULP. In general, cars tested in June perform better than those tested in August, which suggested that mileage was the key criterion of car performance on the basis of elemental emission factors.

4840744 Modified succinimides and lubricating oil compositions containing the same

Disclosed are additives which are useful as dispersants in lubricating oils, gasolines, marine crankcase oils and hydraulic oils. In particular, disclosed are polyamino alkenyl or alkyl succinimides which contain carbamate functionalities.

Development of Additives and Lubricating Oil Compositions

Development of Additives and Lubricating Oil Compositions