Heat release and engine performance effects of soybean oil ethyl ester blending into diesel fuel

The engine performance impact of soybean oil ethyl ester blending into diesel fuel was analyzed employing heat release analysis, in-cylinder exergy balances and dynamometric tests. Blends with concentrations of up to 30% of soybean oil ethyl ester in volume were used in steady-state experiments conducted in a high speed turbocharged direct injection engine. Modifications in fuel heat value, fuel-air equivalence ratio and combustion temperature were found to govern the impact resulting from the addition of biodiesel on engine performance. For the analyzed fuels, the 20% biodiesel blend presented the best results of brake thermal efficiency, while the 10% biodiesel blend presented the best results of brake power and sfc (specific fuel consumption). In relation to mineral diesel and in full load conditions, an average increase of 4.16% was observed in brake thermal efficiency with B20 blend. In the same conditions, an average gain of 1.15% in brake power and a reduction of 1.73% in sfc was observed with B10 blend.     

Biodiesel production from waste cooking oil using heterogeneous catalysts and its operational characteristics on variable compression ratio CI engine

In the present work, the optimum biodiesel conversion from waste cooking oil to biodiesel through transesterification method was investigated. The base catalyzed transesterification under different reactant proportions such as the molar ratio of alcohol to oil and mass ratio of catalyst to oil was studied for optimum production of biodiesel. The optimum condition for base catalyzed transesterification of waste cooking oil was determined to be 12:1 and 5 wt% of zinc doped calcium oxide. The fuel properties of the produced biodiesel such as the calorific value, flash point and density were examined and compared to conventional diesel. The properties of produced biodiesel and their blend for different ratios (B20, B40, B60, B80 and B100) were comparable with properties of diesel oil and ASTM biodiesel standards. Tests have been conducted on CI engine which runs at a constant speed of 1500 rpm, injection pressure of 200 bar, compression ratio 15:1 and 17.5, and varying engine load. The performance parameters include brake thermal efficiency, brake specific energy consumption and emissions parameters such as Carbon monoxide (CO), Hydrocarbon (HC), Oxides of Nitrogen (NOx) and smoke opacity varying with engine load (BP). Diesel engine's thermal performance and emission parameters such as CO, HC, and NOx on different biodiesel blends demonstrate that biodiesel produced from waste cooking oil using heterogeneous catalyst was suitable to be used as diesel oil blends and had lesser emissions as compared to conventional diesel.     

A study on the performance and emission of a diesel engine fueled with Jatropha biodiesel oil and its blends

Biodiesel either in neat form or as a mixture with diesel fuel is widely investigated to solve the twin problem of depletion of fossil fuels and environmental degradation. The main objective of the present study is to compare performance, emission and combustion characteristics of biodiesel derived from non edible Jatropha oil in a dual fuel diesel engine with base line results of diesel fuel. The performance parameters evaluated were: brake thermal efficiency, brake specific fuel consumption, power output. As a part of combustion study, in-cylinder pressure, rate of pressure rise and heat release rates were evaluated. The emission parameters such as carbon monoxide, carbon dioxide, un-burnt hydrocarbon, oxides of nitrogen and smoke opacity with the different fuels were also measured and compared with base line results. The different properties of Jatropha oil after transestrification were within acceptable limits of standards as set by many countries. The brake thermal efficiency of Jatropha methyl ester and its blends with diesel were lower than diesel and brake specific energy consumption was found to be higher. However, HC, CO and CO₂ and smoke were found to be lower with Jatropha biodiesel fuel. NO_x emissions on Jatropha biodiesel and its blend were higher than Diesel. The results from the experiments suggest that biodiesel derived from non edible oil like Jatropha could be a good substitute to diesel fuel in diesel engine in the near future as far as decentralized energy production is concerned. In view of comparable engine performance and reduction in most of the engine emissions, it can be concluded and biodiesel derived from Jatropha and its blends could be used in a conventional diesel engine without any modification.     

The effects of turbocharger on the performance and exhaust emissions of a diesel engine fuelled with biodiesel

This paper investigates the effects of turbocharger on the performance of a diesel engine using diesel fuel and biodiesel in terms of brake power, torque, brake specific consumption and thermal efficiency, as well as CO and NO_x emissions. For this aim, a naturally aspirated four-stroke direct injection diesel engine was tested with diesel fuel and neat biodiesel, which is rapeseed oil methyl ester, at full load conditions at the speeds between 1200 and 2400 rpm with intervals of 200 rpm. Then, a turbocharger system was installed on the engine and the tests were repeated for both fuel cases. The evaluation of experimental data showed that the brake thermal efficiency of biodiesel was slightly higher than that of diesel fuel in both naturally aspirated and turbocharged conditions, while biodiesel yielded slightly lower brake power and torque along with higher fuel consumption values. It was also observed that emissions of CO in the operations with biodiesel were lower than those in the operations with diesel fuel, whereas NO_x emission in biodiesel operation was higher. This study reveals that the use of biodiesel improves the performance parameters and decreases CO emissions of the turbocharged engine compared to diesel fuel.     

The experimental study on the performance,combustion and emission characteristics of a diesel engine using diesel – biodiesel – diethyl ether blends

ABSTRACT

In the present research work, the experimental analysis has been executed to investigate the influence of diethyl ether as an oxygenated additive to the diesel-biodiesel blend on the performance, combustion and emission characteristics of a diesel engine. The biodiesel (Frying oil methyl ester) was prepared by the transesterification process, and the biodiesel was added (40% by volume) to the diesel fuel to prepare the diesel-biodiesel blend (D60FME40). The diethyl ether was added to the diesel-biodiesel blends D60FM35 (diesel 60% + biodiesel 35% by volume) and D60FM30 (diesel 60% + biodiesel 30% by volume) with suitable volume proportions of 5% and 10% respectively to form diesel-biodiesel-diethyl ether blends ((D60FM35DEE5) & (D60FM30DEE10)). Initially, the test was conducted with diesel fuel to obtain the baseline reference reading. Then, the reading was compared with results taken from the engine using a diesel-biodiesel blend (D60FME40) and diethyl ether blends (D60FM35DEE5) & (D60FM30DEE10). The results reveal that the maximum brake thermal efficiency was obtained with diesel fuel and it was higher than the diesel-biodiesel blend and diethyl ether blends. The peak in-cylinder gas pressure and heat release rate in the premixed stage was less for the diesel-biodiesel blend, but it was increased with the addition of diethyl ether to the blend. The diesel-biodiesel-diethyl ether blends show less carbon monoxide and hydrocarbon emissions except for NO_X emission as compared to the diesel and diesel-biodiesel blend, especially at the engine rated power.     

Performance and emission evaluation of a diesel engine fueled with methyl esters of rubber seed oil

Recent concerns over the environment, increasing fuel prices and scarcity of its supply have promoted the interest in development of the alternative sources for petroleum fuels. At present, biodiesel is commercially produced from the refined edible vegetable oils such as sunflower oil, palm oil and soybean oil, etc. by alkaline-catalyzed esterification process. This process is not suitable for production of biodiesel from many unrefined non-edible vegetable oils because of their high acid value. Hence, a two-step esterification method is developed to produce biodiesel from high FFA vegetable oils. The biodiesel production method consists of acid-catalyzed pretreatment followed by an alkaline-catalyzed transesterification. The important properties of methyl esters of rubber seed oil are compared with other esters and diesel. Pure rubber seed oil, diesel and biodiesel are used as fuels in the compression ignition engine and the performance and emission characteristics of the engine are analyzed. The lower blends of biodiesel increase the brake thermal efficiency and reduce the fuel consumption. The exhaust gas emissions are reduced with increase in biodiesel concentration. The experimental results proved that the use of biodiesel (produced from unrefined rubber seed oil) in compression ignition engines is a viable alternative to diesel.     

6BTA 5.9 G2-1 Cummins engine performance and emission tests using methyl ester mahua (Madhuca indica) oil/diesel blends

Neat mahua oil poses some problems when subjected to prolonged usage in CI engine. The transesterification of mahua oil can reduce these problems. The use of biodiesel fuel as substitute for conventional petroleum fuel in heavy-duty diesel engine is receiving an increasing amount of attention. This interest is based on the properties of bio-diesel including the fact that it is produced from a renewable resource, its biodegradability and potential to exhaust emissions. A Cummins 6BTA 5.9 G2- 1, 158 HP rated power, turbocharged, DI, water cooled diesel engine was run on diesel, methyl ester of mahua oil and its blends at constant speed of 1500 rpm under variable load conditions. The volumetric blending ratios of biodiesel with conventional diesel fuel were set at 0, 20, 40, 60, and 100. Engine performance (brake specific fuel consumption, brake specific energy consumption, thermal efficiency and exhaust gas temperature) and emissions (CO, HC and NOx) were measured to evaluate and compute the behavior of the diesel engine running on biodiesel. The results indicate that with the increase of biodiesel in the blends CO, HC reduces significantly, fuel consumption and NOx emission of biodiesel increases slightly compared with diesel. Brake specific energy consumption decreases and thermal efficiency of engine slightly increases when operating on 20% biodiesel than that operating on diesel.     

Investigation on performance,combustion and emission characteristics of biodiesel - Ethanol blends with hydrogen in CI engine

The current research work focus on the utilization of hydrogen as a fuel in CI engine has been increased tremendously, since it is a zero-emission fuel. But higher self-ignition temperature than conventional fuel, makes to operate in dual fuel mode condition in CI engine. The diesel or biodiesel along with hydrogen in a CI engine results in the improvement in the performance but increase of NO. In order to minimize the NO emission, addition of ethanol with jamun B20 biodiesel blend (biodiesel-diesel-ethanol) and two ternary blends such as B20E05 and B20E10 are formed. In the present study, biodiesel along with H₂ is admitted in the CI engine. Ethanol addition reduces combustion temperature and act as cetane improver for the biodiesel. This induces better combustion of the fuel and reduce NO. The biodiesel production from jamun seed is carried out through transesterification process. H₂ of 4 lpm is allowed at the air inlet and jamun B20 blend is injected through the fuel injector. Improvement of brake thermal efficiency and increase in the NO are observed for the hydrogen with biodiesel operated CI engine. The performance and emission behaviors of CI engine done for the test samples. At full load condition (ternary blend) B20E05 assisted H₂ shows the drastic reduction of NO emission of 8.2% than B20 assist H₂ blend. In other hand emission like hydrocarbon, carbon monoxide and smoke opacity show a notable reduction for B20E05 blend assist H₂ than other test sample fuel. The thermal efficiency is 30.98% for B20E05 assist H₂ and it is 7.55% and 4.7% higher than B20 and B20E05 assist H₂ blend respectively.     

Exergy analysis of small DI diesel engine fueled with waste cooking oil biodiesel

ABSTRACT

This study investigates the merits of exergy analysis over energy analysis for small direct injection (DI) diesel engine using the blend of waste cooking oil biodiesel and petroleum diesel. Taguchi’s “L’ 16” orthogonal array has been used for the design of experiment. The engine tested at different engine speeds, load percentages, and blend ratios, using the waste cooking oil biodiesel. Basic performance parameters and fuel input exergy, exergetic efficiency (second law efficiency), exergy associated with heat transfer, exergy associated with the exhaust gas and destruction of exergy are calculated for each blend of waste cooking oil biodiesel and diesel. Results show that the optimum operating conditions for minimum brake-specific fuel consumption (BSFC) and exergy destruction are achieved when engine speed at 1900 rev/min, load percentage is 75%, and the engine is fueled with B40.     

Effect of induction on exhaust gas recirculation and hydrogen gas in compression ignition engine with simarouba oil in dual fuel mode

Biofuels extracted from non-edible oil is sustainable and can be used as an alternative fuel for internal combustion engines. This study presents the performance, emission and combustion characteristic analysis by using simarouba oil (obtained from Simarouba seed) as an alternative fuel along with hydrogen and exhaust gas recirculation (EGR) in a compression ignition (CI) engine operating on dual fuel mode. Simarouba biofuel blend (B20) was prepared on volumetric basis by mixing simarouba oil and diesel in the proportion of 20% and 80% (v/v), respectively. Hydrogen gas was introduced at the flow rate of 2.67 kg/min, and EGR concentration was maintained at 30% of total air introduction. Performance, combustion and emission characteristics analysis were examined with biodiesel (B20), biodiesel with hydrogen substitution and biodiesel, hydrogen with EGR and were compared with neat diesel operation. Results indicate that BTE of the engine operating with biodiesel B20 was decreased when compared to neat diesel operation. However, introducing hydrogen along with B20 blend into the combustion chamber shows a slight increase in the BTE by 1%. NO_x emission was increased to 18.13% with the introduction of hydrogen than that of base fuel (diesel) operation. With the introduction of EGR, there is a significant reduction in NO_x emission due to decrease in in-cylinder temperature by 19.07%. A significant reduction in CO, CO_2, and smoke emissions were also noted with the introduction of both hydrogen and EGR. The ignition delay and combustion duration were increased with the introduction of hydrogen, EGR with biodiesel than neat diesel operation. Hence, the proposed biodiesel B20 with H₂ and EGR combination can be applied as an alternative fuel in CI engines.     

Effects of oxyhydrogen on the CI engine fueled with the biodiesel blends: A performance,combustion and emission characteristics study

The main purpose of this study is to analyse the effects of oxy hydrogen (HHO) along with the Moringa oleifera biodiesel blend on engine performance, combustion and emission characteristics. HHO gases were generated using the typical electrolysis process using the potassium hydroxide solution. The experiments were performed under various engine loads of 25%, 50%, 75%, and 100% in a constant speed engine. Biodiesel from the M. oleifera was prepared by the transesterification process. Further, the procured biodiesel blends mixed with neat diesel at the concentration of 20% (B20) and 40% (B40). In addition to above, the HHO gas flow rate to the engine chamber maintained at the flow rate of 0.5 L^-1. The use of the 20% and 40% blends with HHO reported less BTE compared to the neat diesel. However, B20 reported marginal rise in the BTE due to the addition of the HHO gas. On the other hand, addition of HHO gas to the blends significantly dropped the brake specific fuel consumption. With regard to the emissions, addition of the biodiesel blends reduced the concentration of the CO, HC, and CO₂. Nevertheless, no reduction reported in the formation of the NO. However, adding the HHO to the biodiesel reduced the average NOx by 6%, which is a substantial effect. Overall, HHO enriching biodiesel blends are the potential replacement for the existing fossil fuels for its superior fuel properties compared to the conventional diesel.     

A nonlinear regression based multi-objective optimization of parameters based on experimental data from an IC engine fueled with biodiesel blends

This study reports the results of an experimental investigation of the performance of an IC engine fueled with a Karanja biodiesel blends, followed by multi-objective optimization with respect to engine emissions and fuel economy, in order to determine the optimum biodiesel blend and injection timings complying with Bharat Stage II emission norms. Nonlinear regression has been used to regress the experimentally obtained data to predict the brake thermal efficiency, NO_x, HC and smoke emissions based on injection timing, blend ratio and power output. To acquire the data, experimental studies have been conducted on a single cylinder, constant speed (1500 rpm), direct injection diesel engine under variable load conditions and injection timings for neat diesel and various Karanja biodiesel blends (5%, 10%, 15%, 20%, 50% and 100%). Retarding the injection timing for neat Karanja biodiesel resulted in an improved efficiency and lower HC emissions. A tradeoff relationship between the NO_x and smoke emissions is observed, which makes it difficult to determine the optimum blend ratio. The functional relationship developed between the correlating variables using nonlinear regression is able to predict the performance and emission characteristics with a correlation coefficient (R) in the range of 0.95-0.99 and very low root mean square errors. The outputs obtained using these functions are used to evaluate the multi-objective function of optimization process in the 0-20% blend range. The overall optimum is found to be 13% biodiesel-diesel blend with an injection timing of 24°bTDC, when equal weightage is given to emissions and efficiency.     

Effect of hydrogen enrichment in the intake air of diesel engine fuelled with honge biodiesel blend and diesel

In the current investigation, the enrichment of hydrogen with the honge biodiesel blend and diesel is used in a compression ignition engine. The biodiesel is derived from the honge oil and mixed with diesel fuel by 20% (v/v). Thereafter, hydrogen at different volume flow rates (10 and 13 lpm) is introduced into the intake manifold. The outcomes by enrichment of hydrogen on the performance, combustion and emission characteristics are investigated by examining the brake thermal efficiency, fuel consumption, HC, CO, CO₂, NOₓ emissions, in-cylinder pressure, combustion duration, and rate of heat release. The engine fuelled with honge biodiesel blend is found to enhance the thermal efficiency, combustion characteristics. Compare to diesel, the BTE increased by 2.2% and 6% less fuel consumption for the HB20 + 13H₂ blend. Further, reduction in the emission of exhausts gases like CO and HC by 21% and 24%, respectively, are obtained. This is due to carbon-free structure in hydrogen. Moreover, due to high pressure in the cylinder, there is a slight increase in oxides of nitrogen emission compare to diesel. The combustion characteristics such as rate of heat release, combustion duration, and maximum ₂rate of pressure rise and in-cylinder pressure are high due to hydrogen.     

A cycle simulation model for predicting the performance of a diesel engine fuelled by diesel and biodiesel blends

Among the alternative fuels, biodiesel and its blends are considered suitable and the most promising fuel for diesel engine. The properties of biodiesel are found similar to that of diesel. Many researchers have experimentally evaluated the performance characteristics of conventional diesel engines fuelled by biodiesel and its blends. However, experiments require enormous effort, money and time. Hence, a cycle simulation model incorporating a thermodynamic based single zone combustion model is developed to predict the performance of diesel engine. The effect of engine speed and compression ratio on brake power and brake thermal efficiency is analysed through the model. The fuel considered for the analysis are diesel, 20%, 40%, 60% blending of diesel and biodiesel derived from Karanja oil (Pongamia Glabra). The model predicts similar performance with diesel, 20% and 40% blending. However, with 60% blending, it reveals better performance in terms of brake power and brake thermal efficiency.     

Performance of a diesel engine fueled by waste cooking oil biodiesel

A direct injection diesel engine fueled by a diesel/biodiesel blend from waste cooking oil up to B100 (a blend of 100% biodiesel content) indicated a combustion efficiency rise by 1.8% at full load. The soot peak volume fraction was reduced by 15.2%, while CO and HC concentrations respectively decreased by 20 and 28.5%. The physical and chemical delay periods respectively diminished by 1.2 and 15.8% for engine noise to pronounce 6.5% reduction. Injection retarding by 5° reduced NO_x to those original levels of B0 (a blend of zero biodiesel content) and combined respective reduction magnitudes of 10 and 7% in CO and HC at 75% load. Increasing the speed reduced CO and HC respectively by 26 and 42% at 2.36 times the droplet average strain rate. By coupling the turbulence model to the spray break-up and chemical kinetics models, increasing the injection pressure simultaneously reduced CO, HC and NO_x at 17% exhaust gas recirculation ratio.     

Combustion of fat and vegetable oil derived fuels in diesel engines

In this article, the status of fat and oil derived diesel fuels with respect to fuel properties, engine performance, and emissions is reviewed. The fuels considered are primarily the methyl esters of fatty acids derived from a variety of vegetable oils and animal fats, and referred to as biodiesel. The major obstacle to widespread use of biodiesel is the high cost relative to petroleum. Economics of biodiesel production are discussed, and it is concluded that the price of the feedstock fat or oil is the major factor determining biodiesel price.Biodiesel is completely miscible with petroleum diesel fuel, and is generally tested as a blend. The use of biodiesel in neat or blended form has no effect on the energy based engine fuel economy. The lubricity of these fuels is superior to conventional diesel, and this property is imparted to blends at levels above 20 vol%. Emissions of PM can be reduced dramatically through use of biodiesel in engines that are not high lube oil emitters. Emissions of NO_x increase significantly for both neat and blended fuels in both two- and four-stroke engines. The increase may be lower in newer, lower NO_x emitting four-strokes, but additional data are needed to confirm this conclusion. A discussion of available data on unregulated air toxins is presented, and it is concluded that definitive studies have yet to be performed in this area. A detailed discussion of important biodiesel properties and recommendations for future research is presented. Among the most important recommendations is the need for all future studies to employ biodiesel of well-known composition and purity, and to report detailed analyses. The purity levels necessary for achieving adequate engine endurance, compatibility with coatings and elastomers, cold flow properties, stability, and emissions performance must be better defined.     

Combustion and performance evaluation of a diesel engine fueled with biodiesel produced from soybean crude oil

In this study, the biodiesel produced from soybean crude oil was prepared by a method of alkaline-catalyzed transesterification. The important properties of biodiesel were compared with those of diesel. Diesel and biodiesel were used as fuels in the compression ignition engine, and its performance, emissions and combustion characteristics of the engine were analyzed. The results showed that biodiesel exhibited the similar combustion stages to that of diesel, however, biodiesel showed an earlier start of combustion. At lower engine loads, the peak cylinder pressure, the peak rate of pressure rise and the peak of heat release rate during premixed combustion phase were higher for biodiesel than for diesel. At higher engine loads, the peak cylinder pressure of biodiesel was almost similar to that of diesel, but the peak rate of pressure rise and the peak of heat release rate were lower for biodiesel. The power output of biodiesel was almost identical with that of diesel. The brake specific fuel consumption was higher for biodiesel due to its lower heating value. Biodiesel provided significant reduction in CO, HC, NO_x and smoke under speed characteristic at full engine load. Based on this study, biodiesel can be used as a substitute for diesel in diesel engine.     

Optimisation of dry cell electrolyser and hydroxy gas production to utilise in a diesel engine operated with blends of orange peel oil in dual-fuel mode

This study aims at producing hydroxy (HHO) gas using a dry cell electrolysis setup and utilising it along with orange oil in a diesel engine. First an electrolyser was designed considering the optimised values of the material (SS316L), electrolyte (NaOH), and electrode gap (2 mm). Then the biodiesel obtained from the waste orange peels, after transesterification, were blended with diesel at 25 and 50% by vol. The HHO gas was produced by the water electrolysis method by a plate-type electrolyser having a maximum production rate of 2.5 LPM with NaOH as the electrolyte. HHO gas was inducted through the inlet manifold along with the fresh air at a constant rate of 2 LPM with both the biodiesel blends. The performance, emission, and combustion outcomes of the single cylinder diesel engine for different load conditions (0–100%) were tested for all the blends with and without HHO addition. The results showed a considerable increase in brake thermal efficiency of 1.54% at full load condition, with a noticeable decrease in fuel consumption by 11.1% compared to conventional diesel fuel, was achieved for the O25 blend with HHO induction. Moreover, emissions like hydrocarbon, carbon monoxide and smoke were reduced by 17.6, 29.5, and 12.1%, respectively. However, the improvement in combustion outcomes led to the increase in nitrogen oxides emission by 9.67%. This study helped to understand the production process of HHO gas by dry cell electrolyser and its effect on the blend of orange oil methyl ester and diesel in dual-fuel mode.     

The effects of blending diesel,ethanol, and biodiesel

This work investigated the feasibility of using a blend of standard Brazilian diesel (which contains 5% biodiesel) and up to 5% ethanol. The mixture was characterized as fuel and the performance of a diesel engine operating with a blend containing 3% anhydrous ethanol, the maximum percentage of ethanol that did not reduce the cetane number of the fuel below that specified in Brazilian legislation (ANP Resolution 42), was measured. The presence of anhydrous ethanol in the mixture did not cause a significant impact on engine performance as measured by brake power, brake torque, and brake specific fuel consumption tests. The thermal efficiency of the engine used in the tests was slightly higher with standard diesel than with the diesel-biodiesel-ethanol blend.     

Effect of ethanol blending with biodiesel on engine performance and exhaust emissions in a CI engine

The use of biodiesel as an alternative diesel engine fuel is increasing rapidly. However, due to technical deficiencies, they are rarely used purely or with high percentages in unmodified diesel engines. Therefore, in this study, we used ethanol as an additive to research the possible use of higher percentages of biodiesel in an unmodified diesel engine. Commercial diesel fuel, 20% biodiesel and 80% diesel fuel, called here as B20, and 80% biodiesel and 20% ethanol, called here as BE20, were used in a single cylinder, four strokes direct injection diesel engine. The effect of test fuels on engine torque, power, brake specific fuel consumption, brake thermal efficiency, exhaust gas temperature, and CO, CO₂, NO_x and SO₂ emissions was investigated. The experimental results showed that the performance of CI engine was improved with the use of the BE20 especially in comparison to B20. Besides, the exhaust emissions for BE20 were fairly reduced.