Investigation of the effects of exhaust and power loss in dual-fuel six-stroke engine with EGR technology

ABSTRACT

In today’s world, the usage of internal combustion engines is inevitable. Particularly the diesel engines find their importance more than the petrol engines due to their operating cost. But diesel engines have their demerits in the area of exhaust and power loss. Necessary steps have to be taken in order to effectively use the fuel available. In this technical presentation, we have discussed about the utilisation of six-stroke engines which run on dual fuel. The six-stroke engine’s principle resembles a double-stage compressor. By this way, effective compression is done and the need for turbocharger is completely neglected. We have also considered cylinder’s position in a six-stroke engine. As the lubrication and cooling system needs special attention in the case of opposing-type cylinders, we have formulated a better and simple arrangement in which same power is produced, eradicating the lubrication problems. Also, the pollution (NOx) emitted by the diesel engines is also taken into account. We found the solution in the form of dual-fuel and exhaust gas recirculation system. The combusting temperature of the diesel engine is above 2000°F and this is the prime reason for NOx emission. So an alternative fuel which can be combusted below the level of diesel should be used. Moreover, the availability and production cost must be taken into consideration. We found ethanol as a better alternative for diesel. The cold starting of the engine is made easier using a glow plug, which is used to preheat the charge coming inside the combustion chamber.     

Numerical and experimental investigations on a dual fuel HCCI engine by using ethanol as primary fuel and diesel as secondary fuel for NOX reduction and better performance

ABSTRACT

Achieving the new emission norms is a difficult task to today’s compression ignition (CI) engine without any exhaust gas after-treatment technologies. It is necessary to find the practical method which reduces the unsafe emission, with minor modifications of the CI engine. Dual fuel homogeneous charge compression ignition (HCCI) engine has been recognised as one of the solutions to minimise the emissions and achieve higher performance. In the present study the dual fuel HCCI engine mode of operation carried out by supply of ethanol fuel-air mixture to the engine cylinder through the carburetor and diesel fuel is directly injected at the end of compression for the initiation of ignition. Dual fuel HCCI engine is one of the most promising engines suitable for alternative fuels and lower NO_X emissions. An experimental investigation is carried out on dual fuel HCCI engine. Fuel consumption and exhaust emissions such as NO_X, CO₂, CO, HC are measured and compared with conventional CI engine. The results show that NO_X emission tends to decrease at low and moderate loads of the engine, but at full load condition it is slightly higher. Further, thermal efficiency is calculated and compared in CI engine; it is observed that there is a slight improvement in thermal efficiency at high load operation. In the dual fuel HCCI engine mode, there is a provision to use of ethanol or any other alternate fuel for better energy efficiencies and low NO_X emission.     

Effect of heating the catalytic converter on emission characteristic of gasoline automotive vehicles

Gasoline engines have been widely used as engineering machinery, automobile and shipping power equipment due to their excellent drivability and economy. At the same time, gasoline engines are major contributors to various types of air pollutants such as carbon monoxide (CO), oxides of nitrogen (NO_x), and other harmful compounds. With the increasing concern of environment and more stringent government regulation on exhaust emissions, the reduction in engine emissions such as particulate matter and NO_x is a major research objective in engine development. In this article the effect of heating the catalytic converter on emission characteristic of automotive vehicles in its starting phase of combustion has been studied. In this work, the emission characteristic of hydrocarbons has been improved from 800 to 15 ppm, CO from 4 to 0.07 (V/V%) and NO_x from 1200 to 115 ppm.     

Synthesis of cracked Mahua oil using coal ash catalyst for diesel engine application

ABSTRACT

In this work, production of hydrocarbon fuel from Mahua oil has been characterised for diesel engine application, by appraising essential fuel processing parameters. As opposed to traditional trans-esterification process, the reported oil was identified by using heterogeneous catalysts, as the latter improves the fuel properties better than the former. Therefore, interest has been taken in utilising heterogeneous catalyst such as Coal fly ash (CFA) for biofuel production process. From the experimental investigation it was observed that performance results such as BTE for B25 blend show marginally lower value to sole fuel at all loads and NO_x emission for B100 blend exhibit significantly lower value than sole fuel. Smoke emission for B25 show the increasing trend that of other blends. However, CO, HC emission for B25 shows the marginal increases when compared to the sole fuel and the combustion analysis of B25 blend showed almost similar trend of sole fuel.     

Investigation on the effect of thermal barrier coating at different dosing levels of cerium oxide nanoparticle fuel on diesel in a CI engine

ABSTRACT

In the recent times, the limitations on the exhaust emissions of the internal combustion engines are becoming increasingly rigorous due to environmental safety. Carbon monoxide, oxides of nitrogen, particulates and hydrocarbon are the prime noxious waste emitted by diesel engines. This experimental study involves the analysis of engine performance and emission characteristics of a single cylinder diesel engine with yttria- and ceria-stabilised zirconia coating on a cylinder liner and piston head. Varied dosing levels were added to diesel in both uncoated and coated engines. The experiment resulted in noticeable changes in the selected thermal barrier coating and dosing of cerium oxide additive nanoparticle in diesel. A surge of 2.1% in the brake thermal efficiency and downturn of 3% brake-specific fuel consumption when compared to standard diesel mode in the uncoated engine was discerned. Emission level of nitrogen oxide, carbon monoxide and hydrocarbon also underwent a considerable decline.     

Performance and emission characteristics of homogeneous charge compression ignition engine – a review

Homogeneous charge compression ignition (HCCI) engine uses a relatively new mode of combustion technology. In principle, there is no spark plug or injector to assist the combustion process, and the combustion starts at multiple spots once the mixture has reached its auto-ignition temperature. The challenges over the operation of HCCI-mode engines are the difficulties of controlling the auto-ignition of the mixture, operating range, homogeneous charge preparation, cold start, controlling knock and emissions of unburned hydrocarbon (UHC) and carbon monoxide (CO), which needed to be overcome to achieve successful operation of HCCI-mode engine. This paper reviews the working principle of HCCI-mode engine and analyse the knocking in the HCCI combustion. And it also reviews the impact of homogeneous charge on HCCI combustion parameters, such as heat-release rate and maximum pressure. Furthermore, it reviews the performance and emission characteristics of HCCI engine. For each of these parameters, the theories are discussed about successful operation of HCCI engine with comparative evaluation of performance and emission reported in the literature.     

Application of fuzzy logic in internal combustion engines to predict the engine performance

This paper describes an application of fuzzy logic principle for predicting the internal combustion engine performance, emission and combustion characteristics using fish oil biodiesel. Experimental investigations on a single cylinder, constant speed, direct injection diesel engine were carried out under variable load conditions. The performance, emission and combustion characteristics such as brake thermal efficiency, hydrocarbon, exhaust gas temperature, oxides of nitrogen (NO_x), carbon monoxide, smoke, carbon dioxide, ignition delay, combustion delay and maximum rate of pressure rise were considered. Engine performance was measured using an exhaust gas analyser, smoke metre, piezoelectric pressure transducer and crank angle encoder for different fuel blends and engine load conditions. The obtained data were recorded for each experiment and associated data used to develop a multiple inputs and multiple outputs fuzzy logic model. The developed model produced idealised results with the correlation coefficients of 0.988–0.999 and root mean square error, and was found to be useful for predicting the engine performance characteristics with limited number of available data.     

Experimental analysis of DI diesel engine using dual biofuel blended with diesel

ABSTRACT

In recent years, biodiesel has become more attractive as an alternative fuel for diesel engines because of its environmental benefits and the fact is that it is made from renewable resources. The role of biodiesel is not to replace petroleum diesel, biofuels help to improve the economical growth and positive impacts on the environment. The main purpose of this research is to reduce the emission such as carbon monoxide (CO), nitrogen oxides (NO_X), hydrocarbons (HC) and carbon dioxide (CO₂). And to increase the performance characteristics such as break thermal efficiency (BTE), specific fuel consumption (SFC) of diesel engines. Here we used dual biofuel (lemongrass oil plus mint oil) blended with diesel and cerium oxide is added as an additive and undergone the test of engine performance and emission parameters of diesel. The measuring parameters are BTHE, specific fuel conception, CO₂, CO, NO_x and HC.     

Detailed analysis on injection timing retardation and simultaneous technology in a biodiesel-powered compression ignition engine

ABSTRACT

This detailed study focuses mainly on the reduction of oxides of nitrogen emissions from CI engines. It also discusses about other emissions and performance parameters. Injection timing retardation and simultaneous technology methods have been employed for controlling oxides of nitrogen emissions by many researchers. This review paper studies on injection timing retardation and simultaneous technology and its effects on various operating parameters carried out in a biodiesel-powered CI engines. The objective of this work is to find the significance of injection parameters such as retardation of injection timing and simultaneous technology on the various emission parameters. This paper also deals upon the various methods of retardation of injection timing and simultaneous technology to examine the emissions such as HC, CO, NO_x, smoke, and particulate matters. The present study showed that widespread review on CI engine emission characteristics in a CI engine fuelled with biodiesel blends.     

Experimental investigations of direct injection compression ignition engine by using Coconut,and Karanja biodiesel fuels with emulsions of microalgae based antioxidant

The Compression Ignition (CI) engines are playing vital role in the transportation sector; because of their lower maintenance cost even. The practice of Diesel or biodiesel is increasing Green House Gases (GHG) such as NO_x, particulate matter in the environment. Among all GHG emissions, NO_x is most harmful to human, environment. The use of additives in Diesel, biodiesel their blends in CI engine is very well practicing fuel modification technique to reduce GHG emissions. The higher cost of phenol, amine-based antioxidants are causing to increase CI engine operating cost. In this work, to investigate unmodified Direct Injection Compression Ignition engine characteristics. The Mixed culture Microalgae (MCM) biomass particles used as an antioxidant additive in pure Coconut, Karanja biodiesel. The brake thermal efficiency improved because of the explosion of MCM particles. The NO_x emissions reduced due to the absorption of heat from the combustion chamber by microalgae particle.     

Effect of intake air oxygen enrichment for improving engine performance and emissions control in diesel engine

Stringent emission regulations and health awareness about air pollution have led researchers to find alternative means of minimising emissions in diesel engines. In this article, the influence of oxygen enrichment is discussed to determine the effect on diesel engine performance, emission characteristics and combustion characteristics. Normal diesel and oxygen-enriched diesel are used in this experiment. The increase in oxygen concentration led to complete combustion, producing higher thermal efficiency and low harmful emissions. From the results, it is noted that oxygen-enriched diesel fuel showed reduction of CO, HC and smoke emissions, while NOx emission increased.

Abbreviations/Nomenclature DI: direct injection; NOx: oxides of nitrogen; O₂: oxygen; HC: hydrocarbon; PM: particulate matters; CO: carbon monoxide; CO₂: carbon dioxide     

Effect of CNG flow rate on the performance and emissions of a Mullite-coated diesel engine under dual-fuel mode

On the diesel engines that are used to generate power in transportation and industries, many researchers have to deal with major problems of smoke emissions while extracting higher efficiency. There are many studies which reported the exhaust emission reduction strategies from diesel engines by applying new combustion methods that are capable of mitigating the formation of harmful emissions. One of the methods to reduce the exhaust emissions in diesel engines is to use the dual-fuel combustion mode. In this study, an attempt has been made to evaluate the effect of thermal barrier coating (TBC) on the dual-fuel engine and for this, experiments are carried out on a single-cylinder direct-injection diesel engine under dual-fuel and low heat rejection mode with compressed natural gas (CNG) as gaseous fuel. Engine components that are exposed to the combustion are coated with Mullite (3Al₂O₃-2SiO₂) TBC. Diesel at 200 bar injector opening pressure was used as pilot fuel and CNG at different flow rates (5, 10 and 15 litres per minute) was inducted into the combustion chamber through inlet manifold as main fuel. Experimental results show that the coating of TBC on the engine components has a positive effect on the performance emissions of the dual-fuel test engine. Brake specific fuel consumption (BSFC) was found improved significantly at all flow rates of CNG with coated engine. Emissions on the other hand were also noticed to be on the lower side with the coated engine except NO_x. Smoke emissions were significantly reduced with coated CNG operation of the test engine at all flow rates.     

Experimental study on performance,combustion and emission characteristics of a four-stroke diesel engine using blended fuel

In day today's applications, it is obligatory to devise the usage of diesel in an economic and environmentally benign way. The present work was aimed at studying the performance, emission and combustion characteristics of a four-stroke diesel engine by adding n-pentane at different proportions such as 2%, 4%, 6%, 8% and 10% by volume with diesel. The performance, combustion and emission characteristics obtained from the experiment revealed that the addition of n-pentane augments the brake thermal efficiency of the engine. At full load, the brake thermal efficiency increased by 3.17% for an addition of 6% n-pentane, 4.31% for an addition of 8% n-pentane and 6.36% for an addition of 10% n-pentane. From the emission test, it was concluded that at full load, the NO_x emission decreased by 8.67% for an addition of 6% n-pentane, 17.43% for an addition of 8% n-pentane and 18.09% for an addition of 10% n-pentane.     

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     

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.     

Detailed analysis on emission and performance characteristics of neat biofuel-fuelled diesel engine

ABSTRACT

There is an entanglement over the rapid exhaust of fossil fuel and soreness of environmental changes. Biofuels are acting as an alternative resource for petroleum products and also salve of emissions control and engine performance improvement. Scholars have seen the supreme use of bio-fuel apparent, as it will influence greenhouse effect. Investigation results show the diminished heating value in congruence with conventional pabulum, so it had depleted more in brake mean effective-fuel power ratio and proliferated NO_x compared with diesel fuel. The article mainly focuses on the selection – process of biofuel and analysis of performance (BSFC, EGT and brake thermal efficiency), emissions (CO, NO_x, CO₂, PM and HC) and combustion (NHR and CP) of the engine are exclusively discussed and summarised. Finally, stability, opportunity, and restraint of a selection of alternative fuel and investigation and study on the engine were asserted to guide further future exploration and evolution in that domain.     

Effect of injection pressure on the performance and emission characteristics of the CI engine using Vateria indica biodiesel

Vateria indica Linn seeds were found to contain nearly 19% of oil/fat content. This fat is converted into biodiesel by a novel method by the authors at the biodiesel preparation facility at NITK, Surathkal, India. As biodiesel is a promising alternative fuel for petro diesel in compression ignition (CI) engines, this biofuel is tested in a single-cylinder diesel engine. The objective of this work is to find combustion, performance and emission characteristics of a CI engine with diesel and blends of V. indica biodiesel at 180, 200 and 220?bar injection pressures. Blending is done in volumetric ratios of 10%, 15%, 20% and 25% of biodiesel with diesel which are called as B10, B15, B20 and B25. The idea of increasing fuel injection pressure is to promote atomisation and full penetration into the combustion chamber leading to better combustion. Blend B25 showed best thermal efficiency of the order of 33.03% and the least NO_X emission of 1047?ppm at 220?bar injection pressure at 75% load.     

Effect of nano-fuel additive on performance and emission characteristics of the diesel engine using biodiesel blends with diesel fuel

ABSTRACT

Biodiesel as an alternative source of petroleum fuel could reduce the dependence on petroleum products and control pollution problems. These biofuels are derived from various sources and if directly used in the engine it will not completely burn and will cause an increase in the emission level. In this experiment, 20% of rubber seed oil (B20) blended with pure diesel fuel along with aluminium oxide (Al₂O₃) was used in the proportions of 10?, 20 and 30?ppm. The obtained experimental results showed that the brake thermal efficiency was increased and the engine emission was reduced. And the brake-specific fuel consumption was reduced, but the NO_x level increased at the proportion level at 10?ppm of nano additives. This experiment has been carried out in a single cylinder water-cooled engine connected to an electrical dynamometer without engine modification and the injection pressure and timings were maintained at the standard level designed for the engine. The dynamic energy of aluminium oxide blend with the biodiesel improved the combustion characteristics in the engine, and caused a reduction in carbon deposits by 44.8% in the cylinder wall.     

Experimental investigations on the influence of properties of Calophyllum inophyllum biodiesel on performance,combustion, and emission characteristics of a DI diesel engine

The current state of future energy and environmental crises has revitalised the need to find alternative sources of energy due to escalating oil prices and depleting oil reserves. To meet increasing energy requirements, there has been a growing interest in alternative fuels like biodiesel that can become a suitable diesel fuel substitute for compression ignition engine. Biodiesel offers a very promising alternative to diesel fuel, since they are renewable and have similar properties. Calophyllum inophyllum seed oil collected from different restaurants in the Nagapattinam region of South India was converted into methyl esters (biodiesel) by transesterification. Biodiesel produced from C. inophyllum oil was blended with diesel by different volume proportions (25%, 50%, and 75%). Biodiesel and its blends were tested on a direct injection (DI) diesel engine at a constant speed by varying loads from 0% to 100% in steps of 20% to analyse its performance, emission, and combustion characteristics. The results obtained were compared with that of diesel fuel. B25 (27.5%) showed better performance than diesel fuel (26.28%) at full load and B50 showed performances similar to diesel fuel. Smoke density of B25 was slightly (2.6%) higher than that of diesel at full load conditions. At full load, measured carbon monoxide emissions for B25 and B50 were 4% lower than that of diesel. Hydrocarbon emissions for B25 and B100 were 5.37% and 25.8% higher than that of diesel, respectively. Nitrogen oxides (NO_x) emission was lower for all biodiesel blends. NO_x emissions of B100 and B75 were lower than that of diesel by 22.16% and 13.29% at full load, respectively. Combustion profile was smoother, and no knocking problem was observed while operating with biodiesel blends. B75 produced peak cylinder pressure.     

Exploration of carbon deposit on spark plug of stratified charged gasoline direct injection engine

ABSTRACT

Gasoline direct injection (GDI) engines are operating under high temperature and hence fouling of spark plug can cause misfiring followed by carbon deposits in the vicinity of the spark plug. This effect can cause declined engine power output, unburned hydrocarbon emission and also unacceptable high NO _x near the lean flammability limit of gasoline. The objective was to explore carbon deposit on the spark plug and to identify the most suitable operating variable for the stratified charge mode of a GDI. Performance study was conducted on GDI engine on Start of Injection (SOI) angles of 60°, 100° and 140° bTDC with spark advance of MBT of 16°, 18° and 20°, respectively. Carbon deposit on spark plug at each injection angle was studied through scanning electron microscope (SEM) analysis at specified fuel air ratio. It was revealed that from performance and SEM analysis SOI 100° was chosen as the most suitable operating variable for the stratified charged GDI engine operation.