Effect Of Bio-Based Lubricant Towards Emissions And Engine Breakdown Due To Spark Plug Fouling In A Two-Stroke Engine

Two-stroke also known as two-cycle gasoline engine is a spark ignition engine. Its uniqueness to the four-stroke engine is that this engine does not require lubricant sump, which makes construction lightweight and simple. Its lubricant is mixed with gasoline and burnt together during combustion. There are reports which stated that higher spark plug fouling is due to carbon deposition on the spark plug electrodes on a two-stroke engine when compared to the four-stroke. While many factors could have affected this situation, however, in this paper, the effect of mineral and bio-based lubricants towards carbon deposition and emissions are studied and reported. Idle, half and full throttle operation modes had been conducted on a two-stroke, 43 cubic centimeter engine. To keep combustion temperature below self-cleaning temperature on all three modes of operation, a zero-load test was utilized. This situation accelerates the deposition process as low temperature causes incomplete combustion. This could lead to the accumulation of char, unburned fuel, as well as condensed water and acids as the byproducts blanket the spark plug electrodes and the exhaust system. Five samples had been prepared with a commercially available mineral lubricant (T0) as reference. Trimethylolpropane Trioleate, TMPTO derived from plant origin was used as the bio-based candidate. It was then mixed with T0 which created another four lubricant samples namely T10, T15, T20 and T50 with 10%, 15%, 20% and 50% TMPTO accordingly. Results show that mineral lubricant T0 delivers the lowest hydrocarbon HC, carbon monoxide CO and smoke opacity during idle and half throttle operations. However, it exhibits a greasy deposit on the spark plug circumference and dry carbon deposits on its insulator tip. T0 also emits a liquid residue at the exhaust manifold. T10 and T50 show a wet deposit blanketing both electrodes. Severe deposition was recorded by T50 that caused the engine to fail half way with its emissions had the worst recording. T15 and T20 exhibit only dry carbon deposition on the spark plug circumference. However, T20 has outperformed T15 in terms of emissions with lower CO and CO2 emissions during idling and half-throttling. With better emissions than T15 and better carbon deposition than mineral (T0), T20 could be proposed to be used as a commercial two-stroke lubricant

Temperature effect on tribological properties of polyol ester-based environmentally adapted lubricant

The production of pentaerythritol ester (PE) as food grade lubricant base oil was investigated. The properties of formulated lubricant (AWCI) and neopentyl glycol ester (NPGE) were tested – density, viscosity, total acid number, flash point, copper strip corrosion and NOACK. Wear scar diameter (WSD) and coefficient of friction (COF) were analyzed and compared to commercial lubricant (CL). AWCI which comprised of 0.15% Irgalube 349, 0.15% Irgalube TPPT, and 0.1% Irgamet 39 showed excellent lubricant properties with high flash point, low WSD and low COF at all temperatures despite its lower viscosity than the commercial lubricant, CL

Lubricity of bio-based lubricant derived from chemically modified jatropha methyl ester

Many studies have been undertaken with a view to using chemically modified vegetable oil as a bio-based lubricant. This research focused on tribological properties of trimethylolpropane (TMP) ester, which is derived from renewable resource. This TMP ester was produced from jatropha methyl ester; it is biodegradable and has high lubricity properties. Two different conditions of lubrication are being investigated: extreme pressure and anti-wear. It was found that the TMP ester (Jatropha) has better lubricity in terms of wear and friction compared to paraffin oil under extreme pressure conditions. TMP ester (Jatropha) has similar characteristics to fully formulated lubricant (FFL), in terms of the coefficient of friction (CoF). In terms of the anti-wear condition, TMP ester (Jatropha) has the lowest CoF; however it also has the high wear scar diameter. This is due to corrosion and chemical attack

Study of tribological properties of lubricating oil blend added with graphene nanoplatelets

This paper investigates the effects of graphene nanoplatelets (GNPs) as additives in palm-oil trimethylolpropane (TMP) ester blended in polyalphaolefin. Different concentrations of GNPs that were ultrasonically homogenized in blended lubricants consist of 95 vol% polyalphaolefin and 5 vol% TMP ester. Physical properties of the nanolubricants were identified and tribological behaviors of GNP in blended lubricants were studied using standard fourball testing and surface analysis was done on the wear surfaces using scanning electron microscopy and energy-dispersive X-ray techniques. Addition of 0.05 wt% GNP in blended lubricant resulted in the lowest coefficient of friction and wear scar diameter, thus selected as the most suitable concentration of GNP in the blended lubricant. Friction and wear were reduced by 5 and 15% respectively, with the presence of 0.05 wt% GNP in the blended lubricant

Performance and emission characteristics of a diesel engine fueled with palm, jatropha, and moringa oil methyl ester

This paper aims to investigate the diesel engine performance and emission characteristics fueled with moringa biodiesel and compare those with the performance and emission characteristics of palm biodiesel, jatropha biodiesel, and diesel fuel. In this study, only 20% of each biodiesel (described by MB20, PB20, and JB20, respectively) was tested in diesel engine, given that open literature indicates the possible use of biodiesel of up to 20% in a diesel engine without modification. The physical and chemical properties of all fuel samples are also presented and compared with ASTM D6751 standards. A naturally aspirated multi-cylinder, four-stroke direct-injection diesel engine was used to evaluate their performance at different speeds and full load condition. All biodiesel fuel samples reduce brake power (BP) and increase brake-specific fuel consumption (BSFC) than diesel fuel. Engine emission results indicated that blended fuel reduces the average carbon monoxide (CO) and hydrocarbons (HC) emissions except nitric oxides (NO) emissions than diesel fuel. Among the biodiesel-blended fuel, Palm biodiesel showed better performance and minimal emission than jatropha and moringa biodiesel fuel. Although PB20 showed better performance, but performance of MB20 biodiesel blend is comparable with other fuels. Correspondingly, 20% of moringa biodiesel can be used in a diesel engine without any engine modification

Lubricity of bio-based lubricant derived from different chemically modified fatty acid methyl ester

In this research, polyol ester was used as the source of a biolubricant. The trimethylolpropane (TMP) and pentaerythritol ester (PE) were produced from palm oil methyl ester; they are biodegradable and have high lubricity properties. Two different conditions of lubrication were investigated. Under these test conditions, the wear and friction characteristics of different ester samples were measured and compared. The esters derived from PE and TMP had comparable characteristics to the fully formulated lubricant (FFL) in terms of the coefficient of friction (CoF). In terms of the mixed lubrication condition, the PE ester has the lowest CoF

Improvement of cold flow properties of Cocos nucifera and Calophyllum inophyllum biodiesel blends using polymethyl acrylate additive

Biodiesel, which comprises of fatty acid esters, is an alternative fuel for diesel engines. However, biodiesel has poorer cold flow properties (CFPs; i.e., cloud point (CP), cold filter plugging point (CFPP), and pour point (PP)) than diesel fuel. This study aims to reduce the PP, CFPP, and CP of two different biodiesels, namely, Cocos nucifera (coconut) and Calophyllum inophyllum (C. inophyllum), using polymethyl acrylate (PMA) additives. This study also investigates the effect of PMA on other biodiesel properties. Various physicochemical properties were measured and compared with the ASTM D6751 and EN14214 standards. Differential scanning calorimetry was used to observe the crystal behavior of the biodiesel blends. Results showed that 20% of biodiesel blended with diesel (B20) and 0.03 wt% of PMA showed the highest improvement in the CP, PP, and CFPP. This study also investigates the influence of PMA on oxidation stability, flash point, heating value, and kinematic viscosity. These properties of B20 satisfy the ASTM D6751 and EN14214 standards. The process of crystal aggrandizement and the rate of wax crystal precipitation of B20 can be modified by PMA, resulting in enhanced CFPs of the biodiesel blend. Therefore, PMA is an effective cold-flow-improving additive for coconut-based and C. inophyllum-based biodiesel blends. Moreover, the results indicated that 20% coconut and C. inophyllum biodiesel blends with 0.03 wt% of PMA can be used in cold climate areas without any problem in terms of fuel physicochemical quality

Friction and wear characteristics of Calophyllum inophyllum biodiesel

The purpose of this research is to study the tribological characteristics of Calophyllum inophyllum (Cl) biodiesel as lubricity enhancer by using four ball tribometer. CI biodiesel was produced by using transesterification process and the investigated fuels were pure biodiesel (CIB100), 10% (CIB10), 20% (CIB20), 30% (CIB30) and 50% (CIB50) of biodiesel blended with diesel and pure diesel. Experiment was conducted during 300 s with constant temperature at 27 degrees C and constant sliding speed of 1800 rpm at different load of 40 kg, 50 kg, 63 kg and 80 kg for all tested fuels. The elemental analysis for tested fuel was done using multi element oil analyzer (MOA) and worn surfaces of the ball were examined by SEM/EDX analysis. The average result reveals that diesel fuel shows 16% higher friction coefficient (FC) and 40% higher wear scar diameter (WSD) than pure biodiesel (CIB100). From the elemental analysis, it is found that more metal element (25.3 ppm) is added for CIB100 and highest amount of metal elements were decreased for diesel fuel. The formation of oxide and addition of metal elements are extremely low for CIB20 fuel. Surface morphology showed that CIB20 shows the smaller worn surfaces compared to other diesel-biodiesel blend except CIB100. A further increase in the concentration of biodiesel (CIB30, CIB50), the extrusion of metal is quite higher than CIB20; and thus, CIB20 showed auspicious lubricating performance and highest possibility to form lubricating film without breaking down. (C) 2015 Elsevier B.V. All rights reserved

A review on fuel economy standard for motor vehicles with the implementation possibilities in Malaysia

This paper focused on a review of international experiences on fuel economy standard based on technologies available. It also attempts to identify savings possibilities and greenhouse gas (GHG) emissions reductions. It is known that road transport, particularly private cars are responsible for large, and increasing share of transport fuel use and emissions. With the implementation of fuel economy standard and label for motor vehicles, it will reduce the risks of increasing dependency on petroleum-based fuel and will increase the profit to consumers. The GHG emissions, which causing global warming, air pollution, diseases, etc. can be reduced as well. In this regard, advanced technologies such as, engine, transmission, and vehicle technologies may brought significant consumers and social benefits. Studies in developed countries have shown that fuel economy standard is beneficial for the society, government as well as the environment