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In this study, the use of biodiesel from nyamplung oil (Calophyllum Inophyllum) was studied through a transesterification reaction using a heterogeneous catalyst of CaO from limestone originating from Pamekasan, Madura. The composition ratio used between nyamplung oil and methanol in the transesterification reaction was 1:12 (mol/mol) with the addition of 4% CaO catalyst. The biodiesel that is formed is then tested for its performance and emission characteristics in diesel engines with various fuel mixtures between pure diesel and biodiesel (B-10, B-20, B-30, B-40, B-100 and S-100). The test results for biodiesel blends with the highest power produced from B-10, B-20, B-30 and B-100 fuels were 0.26 kW each at a load of 250 watts. While at a load of 500 watts, the highest power is obtained from the B-40 fuel, which is 0.58 kW. The results of performance testing using S-100 fuel obtained the highest power values ​​of 0.27 and 0.58 kW, respectively, with a load of 250 and 500 watts. Performance testing for biodiesel blends, the highest torque value was obtained when using B-10, B-20, B-30 and B-100 fuels, which were 1.65 N.m each with a load of 250 watts. While at a load of 500 watts, the highest torque is obtained on B-40 fuel, which is 3.69 N.m. The fuel S-100 produces torque of 1.71 and 3.69 N.m, respectively, with a load of 250 and 500 watts. Emission gases characteristics of carbon monoxide (CO), nitrogen monoxide (NO) and nitrogen oxides (NOx) showed the lowest concentrations obtained in B-100 fuel were 387 ppm, 92 ppm and 96 ppm, respectively. Meanwhile, the highest concentrations of CO, NO and NOx emissions were produced from pure diesel fuel (S-100), namely 574 ppm, 126 ppm and 132 ppm, respectively.

Castor oil is an alternative fuel as a substitute for diesel fuel. The property that approaches diesel fuel makes jatropha oil help reduce fossil fuel dependence. Abundant raw materials and high cetane properties make castor oil widely used as fuel in diesel engines. This study aims to observe the consumption of fuel and soot emissions produced by diesel engines using a mixture of diesel fuel with castor oil content of 30%. Based on the results of experiments that have been carried out, fuel consumption and soot emissions have increased. The highest increase occurred in SJ30 fuel at 25% loading. Low heating value is a major cause of increased consumption and soot emissions.

To carry out the investigation, a cylinder pressure model was developed based on the position of the crankshaft, engine load, engine speed, and fuel injection time. This model takes into account the maximum number of parameters involved. The accuracy of the model was verified by experimental results. The average error of the cylinder pressure, the average radical of the square of the error of the cylinder pressure, and the average error of maximum pressure were calculated at 1.85%, 3.32, and 0.66% (of maximum pressure), respectively. This model was compared with the model by Conolly and Yagle; the two models are similar in terms of the pressure relating the square of time and the exponential of time. This model appears applicable to other diesel engines. The results of the equation and experimental results were compared and described by a Fourier series, which is indicative of the cylinder pressure level between them.

Palm oil is one of the vegetable oil, which is converted to biodiesel through a transesterification process using methanol as the catalyst. Palm oil biodiesel or palm methyl ester (PME) can be used in diesel engines without any modification, and can be blended with conventional diesel to produce different proportions of PME-diesel blend fuels. The physical properties of PME were evaluated experimentally and theoretically. The effect of using neat PME as fuel on engine performance and emissions was evaluated using a commercial four-cylinder four-stroke IDI diesel engine. The experimental results on an engine operated with PME exhibited higher brake specific fuel consumption in comparison with the conventional fuel. With respect to the in-cylinder pressure and heat release rate, these increased features by over 8.11% and 9.3% with PME compared to conventional diesel. The overall results show that PME surpassed the diesel combustion quality due to its psychochemical properties and higher oxygen content.

Publication devoted to the problem of translation of ship propulsion plant to low-sulfur fuel grades regulated by new International Maritime Organization (IMO) standards. Study and optimization of the physicochemical properties of marine fuels are important components in the work in order to improve energy efficiency and reduce toxic emissions from marine diesel engines. In the article gives the comparative analysis of standards of marine fuels. Using mathematical modeling, established variational indicated process characteristics of the diesel engine by simulating engine work in a wide range of fuels. As the object of the study was used diesel fuel, residual fuel, ethanol, RME and LNG. The aim of this work is to assess the impact of a number of properties of the fuel, in particular elemental chemical composition and calorific value to the energy performance of the working process of the diesel engine. Assessment carried out for the two cases of the diesel engine: the same cycle fuel delivery and implementations of the same indicated work, which is estimated at indicated pressure. The simulation results show that under the conditions of equal cyclic fuel supply differences indicated efficiency for different fuel are in the range 0.04–5%. [ABSTRACT FROM AUTHOR]

In this study, biodiesel (20%)-methanol (5%)-diesel (75%), biodiesel (20%)-methanol (10%)-diesel (70%), biodiesel (20%)- diesel (80%), and standard mineral diesel as a baseline fuel are tested in a multi-cylinder diesel engine. Those biodiesel-alcohol low proportion blends are investigated under the same operating conditions at 20%, 40% and 60% of engine loads to determine the engine performance and emission of the diesel engine. Overall, biodiesel-methanol-diesel blends show higher brake specific fuel consumption than mineral diesel. As methanol proportions in blends increase, NO emissions increase, while CO emissions are reduced. Also, biodiesel-diesel blend with 5% of methanol is more effective than biodiesel blend with 20% for reducing CO emissions. [ABSTRACT FROM AUTHOR]

Heat available in the exhaust gas of a diesel engine can be an important heat source to provide additional power using separate Rankine Cycle (RC). In this current work, experiments were conducted to measure the available exhaust heat from a 40 kW diesel engine generator set. Performance of an available shell and tube heat exchanger using water as the working fluid was conducted. With the available experimental data, computer simulation was carried out to optimize the design of the heat exchanger. This optimized heat exchanger was then used to estimate additional power considering actual turbine efficiency. Two heat exchangers were used for this purpose. One is used to generate vapour and the other to generate super-heated vapour. Two organic fluids namely Ammonia and HFC-134a were used in this study. The water was also used as working fluid to compare the results. The proposed heat exchanger can produce 10%, 9% and 8% additional power by using water, ammonia and HFC-134a as the working fluids respectively. [ABSTRACT FROM AUTHOR]

Abstract: In this paper a single cylinder constant speed air-cooled four-stroke direct injection diesel engine of 4.4kW is selected for the experimental investigations to evaluate the performance and emission characteristics fuelled with Jatropha oil (JTME), and its blends (20%, 40%, 60%, 80% and 100%). The performance parameters are analyzed include Brake thermal efficiency whereas exhaust emissions include oxides of nitrogen, HC, Smoke and CO. The results of the experiment in each case were compared with baseline data of diesel fuel. It concluded that lower blend of biodiesel 20% JTME act as best alternative fuel among all tested fuel at full load condition. The experimental investigations on the effect of 20% Jatropha methyl esters (JTME) with diesel on performance, combustion and emission characteristics of diesel engine with different combustion chamber geometries (Spherical, toroidal and Re-entrant).Brake thermal efficiency for toroidal combustion chamber was found higher than that of other two combustion chambers. Smoke density, carbon monoxide and hydrocarbons was observed slightly lower for toroidal combustion chamber compared to the other two but those are lower when compared with standard diesel (SCC). However, nitrogen oxides were slightly lower for toroidal combustion chamber compared to the other two but it is higher when compared with standard diesel (SCC). [Copyright &y& Elsevier]