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The present work emphasis on to estimate the theoretical findings of energy and exergy analysis of biodiesel fueled with diesel on variable compression ratio engine at various combinations of fuel blend at different compression ratios. This study aims to identify the optimum engine settings based on compression ratio and biodiesel blends. The engine is operated with methyl esters of rubber seed oil and its 20, 40, 60 and 80% blends with diesel on volume basis. The compression ratio is varied from 18:1 to 22:1 at five compression ratios at 80% load in 3.5 kW, 1500 rpm, single cylinder water-cooled direct injection engine. The variables analyzed are energy and exergy potential of fuel input, shaft work, cooling water, maximum pressure, heat release rate, exergy destruction, brake-specific energy consumption, brake thermal efficiency, second law efficiency, entropy generation, exhaust gas temperature and various emissions. It is observed that the combination of CR 20, B20 and B40 at 80% load gives a better performance in thermodynamic analysis of methyl esters of rubber seed oil blended with diesel in VCR engine.

This research work is proposed to test and evaluate the performance, combustion and emission characteristics of variable compression ratio engine fueled with methyl esters of rubber seed oil as biodiesel. Experiments are carried out on variable compression ratio engine by considering the compression ratio, load, fuel blends, injection pressure and supercharging pressure as variables. The response surface method prediction models for indicated mean effective pressure, brake thermal efficiency, specific fuel consumption, exhaust gas temperature, maximum combustion pressure, heat release rate, ignition delay, carbon monoxide, hydrocarbon and nitrogen oxides emission are developed using the experimental results. D -optimality test is carried out to get optimum engine-operating conditions with improved performance and emission. Test is conducted via the fuel blends of 20, 40, 60 and 80% biodiesel with neat diesel, with an injection pressure of 160 bar at a fixed compression ratio of 20 and at different supercharging conditions at 80% load. The results of the experiment are compared with that of diesel, which confirms that significant improvements in performance and emission characteristics are obtained with the help of supercharging. The combustion characteristics of biodiesel blends comprehend with that of standard diesel.

The transportation demand in India is increasing tremendously, which arouses the energy consumption by 4.1 to 6.1% increases each year from 2010 to 2050. In addition, the private vehicle ownership keeps on increasing almost 10% per year during the last decade and reaches 213 million tons of oil consumption in 2016. Thus, this makes India the third largest importer of crude oil in the world. Because of this problem, there is a need of promoting the alternative fuels (biodiesel) which are from different feedstocks for the transportation. This alternative fuel has better emission characteristics compared to neat diesel, hence the biodiesel can be used as direct alternative for diesel and it can also be blended with diesel to get better performance. However, the effect of compression ratio, injection timing, injection pressure, composition-blend ratio and air-fuel ratio, and the shape of the cylinder may affect the performance and emission characteristics of the diesel engine. This article deals with the effect of compression ratio in the performance of the engine while using Honne oil diesel blend and also to find out the optimum compression ratio. So the experimentations are conducted using Honne oil diesel blend-fueled CI engine at variable load conditions and at constant speed operations. In order to find out the optimum compression ratio, experiments are carried out on a single-cylinder, four-stroke variable compression ratio diesel engine, and it is found that 18:1 compression ratio gives better performance than the lower compression ratios. Engine performance tests were carried out at different compression ratio values. Using experimental data, regression model was developed and the values were predicted using response surface methodology. Then the predicted values were validated with the experimental results and a maximum error percentage of 6.057 with an average percentage of error as 3.57 were obtained. The optimum numeric factors for different responses were also selected using RSM.

For an extensive stretch of time, diesel motors have turned into the world’s “Central player” of transportation. However, fuel consumption, late natural concerns, and accordingly consistently expanding fuel costs have made the quest for another fuel basic. Scientists have shown an enormous interest in testing different plant and vegetable oils as an enhancement for diesel. This foundation Nox discharge is conveyed during the ignition of energizes at high temperatures. Inordinate NOx discharge has a scope of consequences for human wellbeing and the environment. In this article, we will talk about elective energy sources in contrast with petroleum derivatives utilizing the ASTM standard. Thus, in this specific occasion, we’re subbing waste cooking oil and Juliflora oil for nano-added substances like magnesium oxide (MgO) and ferrofluid (Fe3O4). The two oils are mixed in the accompanying rates: 10%, 20%, 30%, and 40%. The SBU Variable Compression Ratio Engine was utilized to execution examination, burning, and outflow attributes. Therefore, we can see a diminishing in HC, a break in warm execution, and an increment in NOx.

Rapid exploration and lavish consumption of underground petroleum resources have led to the scarcity of underground fossil fuels moreover the toxic emissions from such fuels are pernicious which have increased the health hazards around the world. So the aim was to find an alternative fuel which would meet the requirements of petroleum or fossil fuels. Biodiesel is a clean, renewable and bio-degradable fuel having several advantages, one of the most important of which is being its eco-friendly and better knocking characteristics than diesel fuel. In this work the performance of Karanja oil was analyzed on a four stroke, single cylinder, water cooled, variable compression ratio diesel engine. The fuel used was 5% - 25% karanja oil methyl ester by volume in diesel. The results such obtained are compared with standard diesel fuel. Several properties i.e. Brake Thermal Efficiency, Brake Specific Fuel Consumptions, Exhaust Gas Temperature are determined at all operating conditions & at variable compression ratio 17 and 17.5.

The emission and combustion characteristics of a four stroke multi fuel single cylinder variable compression ratio engine fueled with tamanu oil methyl ester and its blends 10%, 20%, 40%, and 60% with diesel (on volume basis) are examined and compared with standard diesel. Biodiesel produced from tamanu oil by trans-esterification process has been used in this study. The experiment has been conducted at a constant engine speed of 1500 rpm with 50% load and at compression ratios of 16:1, 17:1, 18:1, 19:1, and 20:1. With different blend and for selected compression ratio the exhaust gas emissions such as CO, HC, NOx, CO2, and the combustion characteristics are measured. The variation of the emission parameters for different compression ratios and for different blends is given, and optimum compression ratio which gives best performance has been identified. The results indicate higher rate of pressure rise and minimum heat release rate at higher compression ratio for tamanu oil methyl ester when compared with standard diesel. The blend B40 for tamanu oil methyl ester is found to give minimum emission at 50% load. The blend when used as fuel results in reduction of polluting gases like HC, CO, and increase in NOx emissions. The previously mentioned emission parameters have been validated with the aid of artificial neural network. A separate model is developed for emission characteristics in which compression ratio, blend percentage and load percentage were used as the input parameter whereas CO, CO2, HC, and NOx were used as the output parameter. This study shows that there is a good correlation between the artificial neural network predicted values and the experimental data for different emission parameters.

VCC (variable combustion chamber) piston technology would be one of the best substitutes for VCR (variable compression ratio) technology due to its extremely fast dynamic response with simple structure. One of the key issues of VCC piston technology is its dynamic response, which means fast, timely and enough variation of the combustion chamber volume during combustion in each working cycle while excess in-cylinder pressure occurs. Two key design features, ball-profiles and a reset cam, are introduced in order to ensure the availability of transient dynamic characteristics of VCC piston. Several formulas are derived from the structural analysis on VCC piston to describe the relationship between VCC piston design and its dynamic characteristics. By means of ADAMS dynamic simulation, the affecting factors on the dynamic characteristics of VCC piston, including stiffness, friction, damping, contacting conditions and engine working conditions, are investigated, and the effects of pre-tightening force and the design features on the dynamic response are also investigated. The research indicates that (1) the dynamic response of VCC piston is very fast due to the design features of both ball-profiles and reset cam, and (2) by means of VCC displacement (the relative movement between the piston crown and the piston skirt), excessive in-cylinder pressure would be limited effectively in each working cycle while a spark-ignition engine running with higher CR (compression ratio), and (3) the dynamic response of VCC piston can be improved by reducing the pre-tightening force of the disc springs properly.

Abstract Increasingly stringent emissions and fuel economy standards have long remained a source of challenges for research in automobile engine technology development towards the more thermally efficient and less polluting engine. Spark ignition (SI) engines have lower part-load efficiency when compared with the diesel engines. The greatest opportunity for improving SI engine efficiency is by way of higher compression ratio, variable valve timing, low friction, reducing throttling losses, boosting, and down-sizing. Variable compression ratio (VCR) technology has long been recognized as a method for improving the fuel economy of SI engines. In order to vary the compression ratio, some method of varying the geometric compression ratio through changing the clearance volume is required. There are several ways of doing this; various patents have been filed and designs presented, including modification of the compression ratio by moving the cylinder head, variation of combustion chamber volume using a secondary piston or valve, variation of piston deck height, modification of connecting rod geometry, moving the crankpin within the crankshaft, and moving the crankshaft axis. The potential of these technologies needs to be evaluated by a trade-off between cost and consumption benefit. This paper reviews the geometric approaches and solutions used to achieve VCR, considers the results of prior research, and forecasts what benefits, if any, a VCR would bring to present engine design.

The present investigation is directed towards synthesis of zinc oxide (ZnO) nanoparticles and steady blending with soybean biodiesel (SBME25) to improve the fuel properties of SBME25 and enhance the overall characteristics of a variable compression ratio diesel engine. The soybean biodiesel (SBME) was prepared using the transesterification reaction. Numerous characterization tests were carried out to ascertain the shape and size of zinc oxide nanoparticles. The synthesized asymmetric ZnO nanoparticles were dispersed in SBME25 at three dosage levels (25, 50, and 75 ppm) with sodium dodecyl benzene sulphonate (SDBS) surfactant using the ultrasonication process. The quantified physicochemical properties of all the fuels blends were in symmetry with the American society for testing and materials (ASTM) standards. Nanofuel blends demonstrated enhanced fuel properties compared with SBME25. The engine was operated at two different compression ratios (18.5 and 21.5) and a comparison was made, and best fuel blend and compression ratio (CR) were selected. Fuel blend SBME25ZnO50 and compression ratio (CR) of 21.5 illustrated an overall enhancement in engine characteristics. For SBME25ZnO50 and CR 21.5 fuel blend, brake thermal efficiency (BTE) increased by 23.2%, brake specific fuel consumption (BSFC) were reduced by 26.66%, and hydrocarbon (HC), CO, smoke, and CO2 emissions were reduced by 32.234%, 28.21% 22.55% and 21.66%, respectively; in addition, the heat release rate (HRR) and mean gas temperature (MGT) improved, and ignition delay (ID) was reduced. In contrast, the NOx emissions increased for all the nanofuel blends due to greater supply of oxygen and increase in the temperature of the combustion chamber. At a CR of 18.5, a similar trend was observed, while the values of engine characteristics were lower compared with CR of 21.5. The properties of nanofuel blend SBME25ZnO50 were in symmetry and comparable to the diesel fuel.

Regardless of the increasingly intensive application of vehicles with electric drives, internal combustion engines are still dominant as power units of mobile systems in various sectors of the economy. In order to reduce the emission of exhaust gases and satisfy legal regulations, as a temporary solution, hybrid drives with optimized internal combustion engines and their associated systems are increasingly being used. Application of the variable compression ratio and diesel fuel injection timing, as well as the tribological optimization of parts, contribute to the reduction in fuel consumption, partly due to the reduction in mechanical losses, which, according to test results, also results in the reduction in emissions. This manuscript presents the results of diesel engine testing on a test bench in laboratory conditions at different operating modes (compression ratio, fuel injection timing, engine speed, and load), which were processed using a zero-dimensional model of the combustion process. The test results should contribute to the optimization of the combustion process from the aspect of minimal particulate matter emission. As a special contribution, the results of tribological tests of materials for strengthening the sliding surface of the aluminum alloy piston and cylinder of the internal combustion engine and air compressors, which were obtained using a tribometer, are presented. In this way, tribological optimization should also contribute to the reduction in particulate matter emissions due to the reduction in fuel consumption, and thus emissions due to the reduction in friction, as well as the recorded reduction in the wear of materials that are in sliding contact. In this way, it contributes to the reduction in harmful gases in the air.