Experimental investigation of engine emissions with marine gas oil-oxygenate blends

This paper investigates the diesel engine performance and exhaust emissions with marine gas oil-alternative fuel additive. Marine gas oil (MGO) was selected as base fuel for the engine experiments. An oxygenate, diethylene glycol dimethyl ether (DGM), and a biodiesel (BD) jatropha oil methyl ester (JOME) with a volume of 10% were blended with the MGO fuel. JOME was derived from inedible jatropha oil. Lower emissions with diesel-BD blends (soybean methyl ester, rapeseed methyl ester etc.) have been established so far, but the effect of MGO-BD (JOME) blends on engine performance and emissions has been a growing interest as JOME (BD) is derived from inedible oil and MGO is frequently used in maritime transports. No phase separation between MGO-DGM and MGO-JOME blends was found. The neat MGO, MGO-DGM and MGO-JOME blends are termed as MGO, Ox10 and B10 respectively. The experiments were conducted with a six-cylinder, four-stroke, turbocharged, direct-injection Scania DC 1102 (DI) diesel engine. The experimental results showed significant reductions in fine particle number and mass emissions, PM and smoke emissions with Ox10 and B10 fuels compared to the MGO fuel. Other emissions including total unburned hydrocarbon (THC), carbon monoxide (CO) and engine noise were also reduced with the Ox10 and B10 fuels, while maintaining similar brake specific fuel consumption (BSFC) and thermal efficiency with MGO fuel. Oxides of nitrogen (NOx) emissions, on the other hand, were slightly higher with the Ox10 and B10 fuels at high engine load conditions.     

A comparative study of performance and combustion characteristics of a CI diesel engine fuelled with B20 biodiesel blends

This paper aims to study the diesel engine performance and combustion characteristics fuelled with Banalities aegyptiaca oil methyl ester, palm oil methyl ester, sesame methyl ester oil, rapeseed methyl ester oil, soybean oil methyl ester and diesel fuel. In this present work, only 20% of each biodiesel blends was tested in diesel engine; stated that the possible use of biodiesel of up to 20% in a diesel engine without modification in literature. A single-cylinder, auxiliary water-cooled and computer-based variable compression ratio diesel engine was used to evaluate their performance at constant speed and at measured load conditions. The performance and combustion tests are conducted using each of the above test fuels, at a constant speed of 5000?rpm. Thus, the varying physical and chemical properties of test fuels against pure diesel are optimised for better engine performance.

Abbreviations: BP: brake power; BSFC: brake-specific fuel consumption; BTE: brake thermal efficiency; CO: carbon monoxide; CP: cylinder pressure; DP: diesel pressure; EGT: exhaust gas temperature; HC: hydrocarbon; HRR: heat release rate; NO _x : nitric oxides; PM: particulate matter; TDC: top dead centre; VCR: variable compression ratio     

Experimental investigation of performance,combustion and emission characteristics of CI engine fuelled with chicha oil biodiesel

As the decreasing availability of the fossil fuel is rising day by day, the search of alternate fuel that can be used as a substitute to the conventional fuels is rising rapidly. A new type of biofuel, chicha oil biodiesel, is introduced in this work for the purpose of fuelling diesel engine. Chicha oil was transesterified with methanol using potassium hydroxide as catalyst to obtain chicha oil methyl ester (COME). The calorific value of this biodiesel is lower, when compared to that of diesel. The COME and their blends of 20%, 40%, 60% and 80% with diesel were tested in a single cylinder, four stroke, direct injection diesel engine and the performance, combustion and emission results were compared with diesel. The test result indicates that there is a slight increase in brake thermal efficiency and decrease in brake-specific fuel consumption for all blended fuels when compared to that of diesel fuel. The use of biodiesel resulted in lower emissions of CO and HC and increased emissions of CO₂ and NO_x. The experimental results proved that the use of biodiesel (produced from chicha oil) in compression ignition engine is a viable alternative to diesel.     

The use of rapeseed methyl ester biodiesel in diesel engines

Biodiesel fuel is made from vegetable oil and can be used in existing diesel engines without requiring any modifications. The product is produced by transesterification of vegetable oil which uses alcohol (methanol or ethanol) and is known as methyl ester or ethyl ester. Biodiesel fuel is more environmentally friendly because it is biodegradable. The fuel does not contain sulphur and hence does not produce any sulphurous oxides which are, to a large extent, responsible for acid rain. The fuel does emit CO₂ but since this is absorbed by the plants during growth, it offers a net reduction in overall greenhouse gases relative to fossil fuels. The test results on biodiesel fuels showed high friction power with a net reduction in hydrocarbon emissions. The carbon deposits on the injector were similar to those observed when running on diesel while maximum power output was slightly lower due to low heating value of plant fuels.     

Light vehicle regulated and unregulated emissions from different biodiesels

In this study, the regulated and unregulated emissions profile and fuel consumption of an automotive diesel and biodiesel blends, prepared from two different biodiesels, were investigated. The biodiesels were a rapeseed methyl ester (RME) and a palm-based methyl ester (PME). The tests were performed on a chassis dynamometer with constant volume sampling (CVS) over the New European Driving Cycle (NEDC) and the non-legislated Athens Driving Cycle (ADC), using a Euro 2 compliant passenger vehicle. The objectives were to evaluate the impact of biodiesel chemical structure on the emissions, as well as the influence of the applied driving cycle on the formation of exhaust emissions and fuel consumption. The results showed that NO_x emissions were influenced by certain biodiesel properties, such as those of cetane number and iodine number. NO_x emissions followed a decreasing trend over both cycles, where the most beneficial reduction was obtained with the application of the more saturated biodiesel. PM emissions were decreased with the palm-based biodiesel blends over both cycles, with the exception of the 20% blend which was higher compared to diesel fuel. PME blends led to increases in PM emissions over the ADC. The majority of the biodiesel blends showed a tendency for lower CO and HC emissions. The differences in CO₂ emissions were not statistically significant. Fuel consumption presented an increase with both biodiesels. Total PAH and nitro-PAH emission levels were decreased with the use of biodiesel independently of the source material. Lower molecular weight PAHs were predominant in both gaseous and particulate phases. Both biodiesels had a negative impact on certain carbonyl emissions. Formaldehyde and acetaldehyde were the dominant aldehydes emitted from both fuels.     

Emission characteristics of neat rapeseed oil fuel in diesel engine

Studies show that the combustion of fossil fuel is the main cause of increasing global atmospheric carbon dioxide (CO₂) levels, which is the cause of the greenhouse effect. This has promoted increased research world-wide in a bid to source a greener alternative fuel substitute for conventional fossil fuel. Biofuel appears to be an alternative energy source for diesel engines. Although the combustion of biofuels produces CO₂, the same quantity is absorbed by plants during photosynthesis, hence CO₂ levels are kept in balance. The sulphur content of plant fuels is also low and less than 0.01% by weight compared to 0.05% by weight for diesel fuel. The effect of acid rain is therefore reduced or ameliorated. High viscosity is one of the major problems relating to the direct use of neat vegetable oils as fuels. One method of reducing viscosity is by blending with a low viscosity and volatile fuel. This paper investigates the emission characteristics of neat rapeseed oil and its blend with diesel fuel in a single cylinder unmodified diesel engine. Tests were also conducted on pure diesel fuel so that a comparative assessment could be made. Test results showed reduced hydrocarbon (HC) emissions when running on biofuels. The CO production was higher when running on biofuel at high engine speed and was significantly reduced at low speed operations. The CO₂ emissions were similar for all fuels. The analyses of lubrication oil after the runs on plant fuels showed a net reduction in viscosity.     

Analysis of pre-heated crude palm oil,palm oil methyl ester and its blends as fuel in a diesel engine

Diesel engines are widely used in the surface transport system. They are the main source of economic growth of a nation. Nowadays, awareness of the environment compels people to adopt stringent emission norms. The rapid depletion of fossil fuels and the increase in the emission levels have caused concerns globally. An eco-friendly alternate is required to fulfil the growing demand. This paper focuses on alternate fuels and the importance of choosing palm oil. The energy density and higher cetane number are its major advantages. Also it reduces environmental pollution drastically. The viscosity of palm oil is a problem like other vegetable oils, which affects the fuel spray pattern. It reduces the efficiency of the combustion to a large extent. To overcome the problem, the pre-heating technique and transesterification process are adopted in this work. Performance tests were conducted on a single cylinder, four-stroke, direct injection diesel engine coupled with eddy current dynamometer, and emission was monitored using an AVL exhaust gas analyser. The results indicated that vegetable oil fuels have lower brake thermal efficiency compared to that of diesel. Pre-heated oil and methyl ester showed an appreciable reduction in hydrocarbon (HC) and carbon monoxide (CO) emissions and higher exhaust temperature and nitric oxide (NO_x) emission.     

Impact of partially stabilised zirconia on a single-cylinder diesel engine’s performance,using orange oil methyl ester biodiesel

Exhaustion of crude oil resources, rise in fuel prices and necessity to find less-carbon fuel have encouraged to find an alternative fuel. Biodiesel is characterised by its fuel properties, which may have an adverse effect on performance and emission characteristics of the engine. Thus, it is necessary to trans-esterify the extracted orange oil and make it viable for diesel engine. In the present work, partially stabilised zirconia was used as a thermal barrier coating (TBC) for the combustion chamber components using plasma spray technique. The present study focused on the impact of TBC on performance and emission characteristics of a diesel engine with B1 (20% orange oil methyl ester with 80% diesel) sample and diesel. Increased brake thermal efficiency and reduced brake-specific fuel consumption are observed for B1 in the TBC engine. On comparing with the uncoated engine, the B1 in coated engine exhibited lower carbon monoxide, hydrocarbon, oxides of nitrogen and smoke emissions than diesel.     

Simulation of CI engine flow processes for prediction of performance and emissions with different fuels

Diesel-fuelled direct injection compression ignition engines yield high fuel conversion efficiency due to the use of high compression ratios and thus find their place in varied applications. However, tail pipe emissions of conventional diesel engines are a major source of high levels of oxides of nitrogen (NO_x) and particulate matter. Owing to stringent emission legislation, manufactures and researchers are facing tough competition to make them eco-friendly. The present paper deals with a simulation of extensive numerical experiments carried out on a single-cylinder diesel engine by varying timing of inlet valve closing (25°–55°ABDC) and fuels; rapeseed methyl esters and diesel fuel. For this purpose, a zero-dimensional thermodynamics-based model in C⁺⁺ was developed. The model takes into account the engine speed, fuel injection timing and equivalence ratio, temperature-dependent specific heat ratio and inlet valve close timing. The engine performance is evaluated in terms of thermal efficiency, in-cylinder pressure, heat release rate, and NO and soot emissions. It is observed that a significantly delayed closing of the inlet valve would result in loss of charge, and rapeseed methyl ester could be an attractive and viable alternative to petro-diesel fuel.     

Effect of ethanol on the performance,emission and combustion characteristics of a compression ignition engine fuelled with vegetable oil–diesel blend

Experimental work had been carried out to analyse the effect of ethanol on the performance, emission and combustion characteristic of vegetable oil–diesel blend (50% vol. rapeseed oil and 50% vol. diesel fuel). The vegetable oil–diesel–ethanol blended fuels were prepared by using microemulsification technique and the main properties were measured. The results showed that, with the increase in ethanol volume fraction in the blends, the viscosity and density were decreased and close to those of diesel fuel. The combustion started later; the peak cylinder pressure, peak heat release rate varied significantly under different operating conditions and the corresponding crank angles of the peak values were retarded. There were slightly higher brake-specific fuel consumptions. Smoke and nitrogen oxide emissions were observed to reduce, but carbon monoxide and hydrocarbon emissions were found slightly higher with the increase of ethanol volume fraction under all ranges of engine operating conditions.     

Performance and emissions characteristics of a diesel engine with internal jet piston using biodiesel

The paper reports an attempt to test the feasibility of Jatropha methyl ester as a fuel in the engine fuel of a compression ignition engine (C.I.) with turbulence inducements in the combustion chamber. The inefficient mixing of biodiesel oils with air contributes to incomplete combustion. These problems can be eliminated by enhancing in‐cylinder turbulence by providing two holes on the piston crown (internal jet piston) and esterification of the vegetable oil into biodiesel. The performance characteristics revealed that the brake thermal efficiency of the Jatropha methyl ester with an internal jet piston was higher than with a base engine piston. The internal jet piston operation with Jatropha methyl ester exhibited desirable characteristics for other emissions such as lower carbon monoxide (CO), hydrocarbons (HCs) and smoke. The oxides of nitrogen (NOx) emissions were higher for the internal jet piston with increasing load, compared to the base engine piston.     

Effect of exhaust gas recirculation on a nanoparticle-doped biodiesel- and diesel-blends-fuelled diesel engine

ABSTRACT

This work investigates the effect of adding Cerium oxide nanoparticles at different proportions (30, 60 and 90?ppm) to Calophyllum inophyllum methyl ester and diesel blends (20% CI methyl ester and 80% diesel) in a four-stroke single-cylinder diesel engine. Addition of nanoparticles is a strategy to reduce emission and to improve the performance of the biodiesel. Modified fuels are introduced into the engine by admitting exhaust gas recirculation (EGR) at a rate of 10% and 20% so as to reduce nitrogen oxide (NO_X) emissions from biodiesel and diesel blends. Results revealed a significant reduction in emissions (CO, NO_X, HC and Smoke) at a 10% EGR rate. However, brake thermal efficiency is reduced with an increase in brake-specific fuel consumption at higher EGR rates. Hence, it is observed that 10% EGR rate is an effective method to control the emission of biodiesel and diesel blends without compromising much on engine efficiency.     

A comprehensive study on reduction of NOx emission applying EGR technique in a diesel engine using biodiesel (POME) as fuel with ether-based additives

The energy consumption is increasing rapidly due to population growth, improved living standards and industrialisation. A significant amount of fossil fuels is consumed by the transportation sector, which causes the fast depletion of fossil fuels and environmental pollution. These problems can be overcome by using Biodiesel. This research work aims to reduce the NO_x emission in diesel engines. The literature survey reveals that the use of a fuel additive reduces the emissions by oxygenating the fuel. Among oxygenates, ether proves to behave better than alcohols. Hence, for this present work, two different types of ethers were selected which were not used in earlier occasions. DGME (Diethylene Glycol Monomethyl Ether) and DGMB (Diethylene Glycol Monobutyl Ether) are the two additives selected from the ether group and used as additives with palm oil methyl ester (POME) biodiesel in various proportions and tested in a direct injection compression ignition engine which reduced the emissions. To start with, the engine was run with diesel and subsequently with biodiesel and with the additives. The performance tests were carried out in a single-cylinder, four-stroke, water-cooled engine with and without exhaust gas recirculation (EGR). This engine is coupled with eddy current dynamometer. The use of biodiesel in conventional diesel engines results in substantial reduction in emission of carbon monoxide, particulates and unburned hydrocarbons, but increases NO_x emission. This review focuses on reduction of NO_x emission. Combustion and performance analysis of the engine have also been evaluated.     

Experimental investigation of varying the fuel injection pressure in a direct injection diesel engine fuelled with methyl ester of neem oil

Being a fuel of different origin, the standard design parameters of a diesel engine may not be suitable for methyl ester of neem oil (MENO). So the engine parameters need to be optimised to suit the specific fuel properties. This experimental investigation is to find the effects of one of the engine parameters, that is, fuel injection pressure (FIP) jointly on the performance with regard to brake thermal efficiency (BTE), brake-specific energy consumption (BSEC), and emissions of carbon monoxide, carbon dioxide, hydrocarbon, nitrogen oxides, and smoke intensity with neat MENO as fuel. Comparison of performance and emission test were done for different values of IP to find the best possible IP for the optimum performance and emission. The optimum FIP was found to be 240?bar. It is found that the increase in IP increases the BTE and reduces the BSEC while having lower emissions.     

A characteristic evaluation of alumina–zirconia-coated engine fuelled with punnai methyl ester

All these years, several studies have been carried out to find feasible, viable and dominant alternate source to fossil fuels, with the primary interest of enhancing engine performance and reducing exhaust tail pipe emissions. The present work enumerates the performance and emission characteristics of low-heat rejection engine (LHRE) coated with the alumina–zirconia (Al₂O₃–ZrO₂) composite. Experimental results proved improvement in brake thermal efficiency, brake-specific fuel consumption and well-to-wheel reduction of carbon monoxide, hydrocarbon and smoke emission for coated engine (CE) in comparison with uncoated engine (UCE). Neat diesel, new high-potential punnai methyl ester and its diesel blends were used as test fuels. However, in the experimental study, oxides of nitrogen increased for CE than UCE.     

Experimental investigation on regulated and unregulated emissions of a diesel engine fueled with ultra-low sulfur diesel fuel blended with biodiesel from waste cooking oil

Experiments were conducted on a 4-cylinder direct-injection diesel engine using ultra-low sulfur diesel, bi oesel and their blends, to investigate the regulated and unregulated emissions of the engine under five engine loads at an engine speed of 1800 rev/min. Blended fuels containing 19.6%, 39.4%, 59.4% and 79.6% by volume of biodiesel, corresponding to 2%, 4%, 6% and 8% by mass of oxygen in the blended fuel, were used. Biodiesel used in this study was converted from waste cooking oil.The following results are obtained with an increase of biodiesel in the fuel. The brake specific fuel consumption and the brake thermal efficiency increase. The HC and CO emissions decrease while NO_x and NO₂ emissions increase. The smoke opacity and particulate mass concentrations reduce significantly at high engine load. In addition, for submicron particles, the geometry mean diameter of the particles becomes smaller while the total number concentration increases. For the unregulated gaseous emissions, generally, the emissions of formaldehyde, 1,3-butadiene, toluene, xylene decrease, however, acetaldehyde and benzene emissions increase.The results indicate that the combination of ultra-low sulfur diesel and biodiesel from waste cooking oil gives similar results to those in the literature using higher sulfur diesel fuels and biodiesel from other sources.     

Trends of greenhouse gas emissions from the road transport sector in India

The road transport sector is the largest consumer of commercial fuel energy within the transportation system in India and accounts for nearly 35% of the total liquid commercial fuel consumption by all sectors. Gasoline and diesel consumption for road transportation have quadrupled between 1980 and 2000 due to about nine times increase in the number of vehicles and four-fold increase in freight and passenger travel demands. The paper elaborates the trends of energy consumption and consequent emissions of greenhouse gases such as CO(2), CH(4) and N(2)O and ozone precursor gases like CO, NO(x) and NMVOC in the road transport sector in India for the period from 1980 to 2000. For the first time, efforts have been made to apportion the fuels, both diesel and gasoline, across different categories of vehicles operating on the Indian roads. In order to generate more comprehensive and complete emission estimates, additionally, other minor fuel types like light diesel oil and fuel oil along with lubricants have also been taken into account. Emission estimates have revealed that nearly 27 Mt of CO(2) were emitted in 1980, increasing to about 105 Mt in 2000. Similar trends have also been observed for other gases. Further scope for improvements in emission estimation is possible by generating country specific emission factors for different vehicle categories and improvement in documentation of fuel consumption at segregated levels by fuel types and vehicle types.     

Experimental studies on the performance,emission and combustion characteristics of a biodiesel-fuelled (Pongamia methyl ester) diesel engine with diethyl ether as an oxygenated fuel additive

This paper investigates the combustion, performance and emission characteristics of a single-cylinder diesel engine using neat biodiesel (Pongamia methyl ester) with two different blends (10% and 15% diethyl ether [DEE]) at different load conditions. The measured values of brake thermal efficiency (BTE), brake specific fuel consumption (BSFC), exhaust gas temperature (EGT), carbon monoxide (CO), hydrocarbon (HC), nitrogen oxide (NO) and smoke were calculated and analysed and compared with diesel fuel. The results showed that a significant reduction in NO and smoke emissions for neat biodiesel with 15% DEE blend compared with neat biodiesel at full load conditions. The peak pressure and heat release rate were decreased, and maximum rate of pressure rise and ignition delay were also decreased with DEE blends at full load. On the whole, it is concluded that the biodiesel with 15% DEE blend showed better results with respect to efficiency and emissions point of view compared with biodiesel.     

Bio-ethanol additive effect on direct injection diesel engine performance,emission and combustion characteristics – an experimental examination

ABSTRACT

The present investigation explores the effect of dairy scum oil methyl ester (DSOME) blends and ethanol additive on TV1 Kirloskar diesel engine performance, combustion and emission characteristics. From the experimental study, it is concluded that DSOME-B20 (20% dairy scum biodiesel?+?80% diesel) has shown appreciable performance and lower HC and CO emissions among all other blends. Hence DSOME-B20 is optimised as best fuel blend and it is carried for further investigations to study the effect of bio-ethanol additive on diesel engine performance. From the study it apparent that diesel engine operated with ethanol additive and 20% dairy scum biodiesel blended fuels shown the satisfactorily improved emission characteristics when compared to petroleum diesel fuel operation. Finally, from the experimental investigation, it concludes that addition of ethanol shown the slightly higher HC, CO emission and improved BTE, BSFC, NOx and CO₂ than sole B20 biodiesel blend. Among all three (3%, 6% and 9%) ethanol additive ratios, E6% (6%-ethanol with B20) ethanol additive exhibits slightly better BTE, BSFC, cylinder pressure and heat release rate hence 6% ethanol additive with B20 biodiesel blend would furnish beneficial effects in the diesel engine.     

Effect of exhaust gas recirculation on performance and emission characteristics of a diesel engine fuelled with tamarind biodiesel

The present research work focuses on the influence of exhaust gas recirculation (EGR) on the characteristics of the diesel engine operated with 20% tamarind seed methyl ester (TSME 20) as the renewable fuel. The use of TSME 20 as biodiesel results in closer performance characteristics with diesel fuel. However, TSME 20 biodiesel blend generated higher oxides of nitrogen (NO_X) emissions at all operating conditions. Firstly, tests are performed using diesel and TSME 20 biodiesel blend at constant speed under different loads. Thereafter, experiments are conducted on TSME 20 with EGR rates at different concentrations. The test results revealed that with TSME 20 with 20% EGR rate, NO_X emissions are reduced by 45.67% and 52.69% when compared to diesel and TSME 20. However, there is a slight reduction in brake thermal efficiency. Hence, the use of 20% EGR rate to TSME 20 is an optimum approach for better control of NO_X emissions.

Abbreviations BDC: bottom dead centre; BMEP: brake mean effective pressure; BSFC: brake-specific fuel consumption; BTE: brake thermal efficiency; CO: carbon monoxide; CO₂: carbon dioxide; EGR: exhaust gas recirculation; FSN: filter smoke number; HC: hydrocarbon; kWh: kilo Watt hour; NO_X: oxides of nitrogen; ppm: parts per million; SO: smoke opacity; TDC: top dead centre; TSME: tamarind seed methyl ester; TSME 20: 20% tamarind seed methyl ester; TSME 20–20%: tamarind seed methyl ester with 80% diesel; TSME 10% EGR: TSME 20 with 10% exhaust gas recirculation; TSME 20% EGR: TSME 20 with 20% exhaust gas recirculation; TSME 30% EGR: TSME 20 with 30% exhaust gas recirculation