This paper presents the performance of biodiesel blends in a single-cylinder water-cooled diesel engine. All experiments were carried out at constant speed 1500 rpm and the biodiesel blends were varied from B10 to B100. The engine was equipped with variable compressions ratio (VCR) mechanism. For 100% Jatropha biodiesel, the maximum fuel consumption was 15% higher than that of diesel fuel. The brake thermal efficiency for biodiesel and its blends was found to be slightly higher than that of diesel at various load conditions. The increase in specific fuel consumption ranged from 2.75% to 15% for B10 to B100 fuels. The exhaust gas temperature increased with increased biodiesel blend. The highest exhaust gas temperature observed was 430 ∘ C with biodiesel for load conditions 1.5 kW, 2.5 kW, and 3.5 kW, where as for diesel the maximum exhaust gas temperature was 440 ∘ C. The CO 2 emission from the biodiesel fuelled engine was higher by 25% than diesel fuel at full load. The CO emissions were lower with Jatropha by 15%, 13%, and 13% at 1.5 kW, 2.5 kW, and 3.5 kW load conditions, respectively. The NO emissions were higher by 16%, 19%, and 20% at 1.5 kW, 2.5 kW, and 3.5 kW than that of the diesel, respectively.

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Diesel engines are widely used as power sources for medium and heavy-duty applications because of their lower fuel consumption and lower emissions of carbon monoxide (CO) and unburned hydrocarbons (HC) compared with gasoline engines. Efficient use of natural resources is one of the fundamental requirements for any country to become self-sustainable. Both in organized and unorganized sectors internal combustion engine has become an indispensable prime mover. With the increasing demand on the use of fossil fuels, a stronger threat to clean environment is being posed as the burning of fossil fuels is associated with emissions like CO2, CO, SOx, NOx and particulate matter, which are currently the dominant global source of emissions. In diesel engines, NOx formation is a highly temperature-dependent phenomenon. Therefore, in order to reduce NOx emissions in the exhaust, it is necessary to keep peak combustion temperatures under control. Exhaust gas recirculation is the most important technique for reducing NOx emissions. Re-circulating part of the exhaust gas helps in reducing NOx, but appreciable particulate emissions are observed at high loads, hence there is a trade-off between NOx and smoke emission. To get maximum benefit from this trade-off, a particulate trap may be used to reduce the amount of unburnt particulates in EGR, which in turn reduce the particulate emission also. An experimental investigation was conducted to observe the effect of exhaust gas re-circulation on the exhaust gas temperatures and exhaust opacity. The experimental setup for the proposed experiments was developed on a single-cylinder, direct injection, air-cooled, compression ignition engine. A matrix of experiments was conducted for observing the effect of different quantities of EGR on exhaust gas temperatures and opacity.

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Background:The piezoelectric motion with multi-degree of freedom is gaining attention in industries for modern manufacturing. High degree of positioning accuracy is obtained by complaint micro machining stages which involves high cost. A variety of stages of multi-degree motion freedom are proposed and applied for decades which can perform very high precision outputs in a wide travel range. Methodology: This paper mainly focuses on design, development and analysis of the 3 DOF (Degree of Freedom) XYq Z micro-motion stage. The role of each component of the stage is discussed. The various design processes are discussed and includes the discussion about the inputs to the design process as well as the constraints; both of which are dependent on the application for which the stage is used. Based on the design rules, an iterative optimization process is implemented and three design options are presented. Findings: The finite element modeling of all the design options are carried out. This is followed by performing deformation, static, fatigue and modal analysis on the three design options. The deformation analysis predicts that design 1 and design 2 offer a workspace of around 210 µm each along (X, Y) direction and 25 µrad along the Z direction while design 3 has deformation of 125 µm each along (X, Y) direction while 25 µrad along Z direction where as the fatigue analysis presented shows the life of around 105 cycles. Novelty: Using this technique the micro-motion stage is achieved for three degrees of freedom.