Biodiesel-ethanol Blends Research Articles

A hybrid ANN-Fuzzy approach for optimization of engine operating parameters of a CI engine fueled with diesel-palm biodiesel-ethanol blend

This paper investigates use of artificial neural network (ANN) model in prediction of brake specific energy consumption (BSEC), nitrogen oxides (NOx), unburnt hydrocarbon (UHC), and carbon dioxide (CO2) emissions of a single cylinder diesel engine operates with diesel-palm biodiesel-ethanol blends. The engine is run at different load form 20–100% and 1500 rpm constant speed. The fuel used in this present study are diesel and six different diesel-palm biodiesel-ethanol blends. The Levenberg-Marquardt back propagation training algorithm with logistic-sigmoid activation function results best prediction of performance and emission characteristics with accurate overall correlation coefficient (R) (0.99329–0.99875) and minimum mean square error (MSE) (0.000179082–0.000465809). The mean absolute percentage errors (MAPE) are observed to be in range of 2.32–4.54% with the acceptable margin of mean square relative error (MSRE). Furthermore, experimental and ANN predicted data are compared in fuzzy interface system (FIS) to find optimum engine operating parameters. Compared to other blends, at 20% load, D85BD10E5 blend exhibits the highest MPCI (multi performance characteristics index) values of 0.718 and 0.705 for experimental and ANN predicted data respectively. Robustness and reliability of the proposed techniques clearly explain the application of ANN and fuzzy logic system in the prediction and optimization of engine parameters.

A numerical study on the quasi-steady spray and soot characteristics for soybean methyl ester and its blends with ethanol using CFD-reduced chemical kinetics approach

Abstract This work numerically examines the quasi-steady spray combustion and soot development for soybean methyl ester (SME) and SME-ethanol blends (S90E10, S70E30). A validated reduced ethanol mechanism (37 species and 149 reactions) was formulated using a temperature sensitivity analysis under auto-ignition and jet-stirred reactor conditions. At initial pressures between 10.0 bar and 60.0 bar, initial temperatures between 750 K and 1350 K and equivalence ratios between 0.5 and 2.0, the ignition delays and key species profiles (C2H5OH, CO2, O2) of the reduced mechanism deviated by 0.5 order and 40%, respectively as compared to the experimental measurements. Subsequently, the reduced ethanol mechanism was combined with a reduced biodiesel mechanism to form a surrogate mechanism (102 species and 446 reactions) for biodiesel-ethanol blends and integrated into OpenFOAM for spray combustion modelling. Under reacting spray conditions at a constant ambient density of 22.8 kg/m3 and ambient temperatures of 900 K and 1000 K, the spray penetrations for SME-ethanol blends were shortened by 35.5% (maximum difference). Smaller flame areas with 60 K higher local flame temperature were obtained. Due to a 20% decrease in acetylene mass fractions and soot formation rates, the peak soot volume fractions for SME-ethanol blends were 19.6% lower.

Performance improvement and exhaust emissions reduction in diesel engine through the use of graphene quantum dot (GQD) nanoparticles and ethanol-biodiesel blends

Abstract In the present study, the effects of graphene quantum dot (GQD) nano-particles on performance and emissions of a diesel engine with ethanol-biodiesel blends was investigated. Biodiesel was used in the blend of B10. The GQD nano-particles with concentration of 30 ppm were considered for each fuel blend. Experiments were performed at engine speeds of 1800, 2100 and 2400 rpm. Various parameters, such as power, torque, specific fuel consumption (SFC), carbon monoxide (CO), carbon dioxide (CO2), unburned hydrocarbons (UHC), and nitrogen oxides (NOx), were investigated. The results showed that adding GQD nanoparticles to fuel increased power and torque by 28.18% and 12.42% respectively, and reduced SFC, CO and UHC by 14.35%, 29.54% and 31.12% respectively, compared to D100 fuel. Finally, it can be concluded that GQD nano-particles can be introduced as a suitable alternative fuel additive for ethanol-biodiesel blends. Also, the adding GQD nanoparticles to fuel could be a viable alternative solution to diesel that can effectively address global energy crisis and environmental issues.

Chemical kinetic mechanism for diesel/biodiesel/ethanol surrogates using n-decane/methyl-decanoate/ethanol blends

Diesel–biodiesel–ethanol blends have been the focus of research in engines, as biodiesel and ethanol additives can lower pollutant emissions while maintaining diesel performance. To facilitate modeling and analysis, those complex fuels are often substituted by simplified surrogate fuels, composed of only a few well-characterized molecules, but displaying similar properties compared to the fuel that they represent. In this context, the objective of this paper is to develop and validate a new chemical reaction mechanism for diesel–biodiesel–ethanol surrogate fuels. n-Decane and methyl-decanoate (MD) were chosen as the diesel and biodiesel surrogates, respectively, as they are frequently used in the literature. As the available reduced methyl-decanoate models do not reproduce the negative temperature coefficient behavior found in auto-ignition delay experiments, the detailed MD model of Dievart et al. was reduced using DRGEP. This last model was then combined with the reduced n-decane model due to Chang et al. and that of ethanol due to Marinov. Validations are performed on 0D constant-volume auto-ignition by comparing auto-ignition delay times and 1D freely propagating gaseous premixed flame configurations by analyzing laminar flame speeds, using the original single component kinetic models, against the combined surrogate kinetic models, and experimental results found in the literature. Laminar flame speeds of n-decane/methyl-decanoate/ethanol blends are also presented.

An Investigation of Diesohol-Biodiesel Mixture in Performance-Emission Characteristics of a Single Cylinder Diesel Engine: A Trade-Off Benchmark

The issue of environmental pollution and the depletion of fossil fuel are nowadays a major field of attention for the modern world. In substitution of petroleum-based diesel, biodiesel and ethanol have been explored in many studies. In this paper, diesel-palm biodiesel-ethanol has been used together at different proportion to execute performanceemission characteristics and their trade-off study at different brake power. An experimental investigation is carried out for different diesel-palm biodiesel-ethanol blends ranging by volume of 5-10% ethanol, 5-25% biodiesel and 65-90% baseline diesel. From the experimental results, comparatively, low brake specific fuel consumption (BSEC) has been observed for all 5% ethanol-blended fuels. Maximum reduction in BSEC has been observed 1.9, 2, and 3.24 % at 0.68, 2.05, and 3.42 kW respectively. At medium to high load, brake thermal efficiency (BTE) has been found higher for lower ethanol fraction. As compared to diesel, the highest nitrogen oxide (NOx) reduction have been found 13.7, 9.17, and 4.7 % at 0.68, 2.05, and 3.42 kW respectively. At last, performance-emission trade-off shows that D70B25E5 blend has a higher BTE with maximum reduction in unburnt hydrocarbon (UHC) and NOx emissions.

Experimental investigation of combustion, performance and emission characteristics of a diesel engine fuelled with diesel–biodiesel–alcohol blends

The purpose of this study is to investigate the impacts of diesel–biodiesel–alcohol blends on the combustion, performance and emissions characteristics of a single-cylinder diesel engine. Tests were conducted at different engine speeds of 1750, 2250, 2750 and 3250 rpm and under full load. In this study, different fuels [called as reference diesel (D100), 20 vol% cottonseed methyl ester (D80C20), 10 vol% ethanol (D90E10) and finally the ternary type of their derivations (D70C20E10)], were used. The experimental results showed that the highest reduction values were observed on CO emission by 42%, 30% and 8% for the D90E10, D70C20E10 and D80C20 fuels, respectively. These reductions for HC emission were achieved as 40%, 31% and 23% for the D90E10, D70C20E10 and D80C20, respectively. On the other hand, the reductions of NOx and CO2 emissions were not sharp and varied between 2–7%. Besides the reductions on the exhaust emissions, biodiesel–ethanol blend presented better results in terms of HRRmax and CPmax than using biodiesel alone. Additionally, ignition delay of the biodiesel blends was longer than that of D100 fuel owing to their low cetane numbers. Combustion duration was shortened with the increment in engine speed because the turbulence increased in the combustion chamber at high engine speed. This case also improved the homogeneity of test fuels and increased the quality of the combustion process. As a consequence, this paper clearly reported that it is possible to achieve fewer emissions, the highest CPmax values with the presence of ethanol in biodiesel fuels rather than using biodiesel alone for diesel engines.

Experimental study on the electrospray and combustion characteristics of biodiesel-ethanol blends in a meso-scale combustor

Abstract The spray and combustion characteristics of biodiesel-ethanol blends were experimentally investigated by using electrospray atomization in a meso-scale combustor. Phase Doppler anemometry measurements were employed to obtain droplet size distribution. Optical measurements were carried out to quantify the electrospray structures. With the addition of ethanol, the spray angle increased and the droplet size decreased from 128 μm to 12 μm. The polydisperse spray of the biodiesel-ethanol blends with a low ethanol blending ratio yielded the bimodal distribution in droplet size due to Coulomb fission. Relative standard deviation of monodisperse droplets is below 15%. The combustion of the blends was performed in a meso-scale combustor with a 12 mm inner diameter. The flame can be stabilized near the mesh in the combustor without any external heating. It was found that the spray structures have a direct effect on the flame structures in spray combustion. 40% ethanol addition (BE40) has the best combustion performance compared to other blends. The results show that the flame of BE40 has a broader stabilization limit both in flow velocity and equivalence ratio. The reduction of the droplet size for the blends with high ethanol blending ratio results in the decrease of CO emission.

Effect of biogas on the performance and emissions of diesel engine fuelled with biodiesel-ethanol blends through response surface methodology approach

Fossil fuels consumption rate is an important issue which needs to be addressed regarding future perspectives in terms of the world overall energy requirement due to its exhausting nature and also due to environmental concern. Hence, more diversified research for alternate sources of fuel is needed, even to the extent of using only dual fuels; a mixture of high and low viscous fuel to eliminate diesel from compression ignition (CI) engines completely. In the present study, soya and soya ethanol blends are used as fuels for the CI engine. Besides the use blends in a diesel engine, the response surface methodology technique is also implemented for getting better responses. RSM results confirm that the use of dual fuel results in satisfactory engine performance and emission in a standard diesel engine without any modification in the engine. Blends, engine speed, air flow rate, and engine load are the input variables considered for attaining better BTE, VE, CO, HC, and NO x as the responses. From all the tested fuel blends considered in the study, the result shows that a blend of soya biodiesel with 8% blending with dual fuel mode at 1486 RPM, 49.5 mm manometer air flow, 6.27 kg engine load show an overall good engine performance. The performance and emission characteristics (BTE, VE, CO, HC, and NO x emission) are found to be 24.29%, 68.53%, 0.0715% volume, 51.6 ppmv and 1080.2 ppmv respectively. • Production of biodiesel from the soya oil. • Blended with ethanol and biogas was injected during the performance. • Optimization of the input parameters is carried out using response surface methodology. • Responses are BTE, volumetric efficiency, carbon mono oxide, unburnt hydro carbon and NO x .

Experimental investigation of the autoignition properties of ethanol–biodiesel fuel blends

Growing interest in increasing the market share of renewable fuels results from the increasing consumption of fuels in various industries, especially in road transport. Such fuels include, for example, ethanol and FAME (Fatty Acid Methyl Esters), known as biodiesel. In diesel engines, ethanol, unlike biodiesel, cannot be directly used as a pure fuel due to its very low autoignition propensity. However, due to the good autoignition properties of biodiesel, increasing attention is being paid to the fuel constitution, for example, a blend of biodiesel with ethanol additive. This way, it is possible to obtain fuel for diesel engines that are compositions of only products of plant origin. In this paper, the autoignition properties of RME (Rape Methyl Esters) and ethanol blends, with the ethanol fraction up to 25% (v/v) were examined. A constant volume combustion chamber was used in the study. Under the specified test conditions, the ignition delay period and the combustion delay period, as well as the DCN (Derived Cetane Number), were determined for the individual blends. The average and maximum pressure rise rates in the combustion chamber were also analysed. The study has shown, for example, that with an increase of ethanol fraction in biodiesel, the periods of ignition and combustion delay increase. It was also shown that in the range from 5% (v/v) to 25% (v/v) of the ethanol fraction, for every increase in the fraction of ethanol by 5% (v/v), the DCN of the biodiesel–ethanol blend is reduced by an average of 3.4 units.

Exploration of PROMETHEE II and VIKOR methodology in a MCDM approach for ascertaining the optimal performance-emission trade-off vantage in a hydrogen-biohol dual fuel endeavour

Abstract In order to meet the challenges of global energy insecurity and the increasing obligation of complying with the environmental legislation, a paradigm shift from the reliance of conventional fossil fuel resources in IC engine domains are being increasingly witnessed. Exhaustive research has been carried out with non-conventional and alternative fuels resources in the off-road and transportation sector to meet the challenges of exploring a potential alternative to conventional diesel fuel with the additional objective of meeting the ever increasing stridency of the emission mandates. Among various alternative fuels, hydrogen whose clean and green burning characteristics has proven to be viable, sustainable fuels in IC engine domains with the premium quoting as one of the significant low emission signature than conventional fuels. Biodiesel, on the other hand, presents itself as a ready-to-use sustainable alternative in diesel powertrains in the environment of its National agricultural and rural economic development potential. As hydrogen is deemed to increase NOx emission when it is used with biodiesel, ethanol (20% v/v) blend with biodiesel has been used as a viable NOx suppression measure owing to its superior miscibility in methyl ester in comparison to conventional diesel. To this end, single cylinder diesel engine has been made to operate in a dual fuel mode with hydrogen as the dual fuel and mahua methyl ester with ethanol in blend as pilot fuel. The present aims of the study are to choose the best suitable fuel combination among the alternatives, in relation to various attributes chosen especially with an eye to address the performance-emission trade-off potential of the dual fuel operation. The most appropriate duel fuel combination out of ten alternatives has been discerned through distinct multi-criteria decision making (MCDM) methodologies. Analytic Hierarchy Process (AHP) has been applied for finding the weightage of each criterion and ranks of the alternatives investigated have been calculated by using VIKOR and PROMETHEE II methods. The alternative which signified biodiesel under hydrogen enrichment, at hydrogen injection duration of 9000 µs at a constant engine speed of 1500 RPM, was discerned as the the most appropriate alternative fuel combination at 75% load since it has been ranked first by both the MCDM methods. At full load for PROMETHEE II it was alternative A4, and for VIKOR it was observed as alternative A3 which signified biodiesel under hydrogen enrichment at hydrogen injection duration of 7000 µs at 1500 RPM. Alternatively, A10 strategy which indicate biodiesel ethanol blend along with hydrogen enrichment at hydrogen injection duration of 13,000 µs at 1500 RPM was observed to be the least preferential amongst the alternative for both the MCDM methods, at both 75% and 100% loads. Since there was consistency in the ranking, in order to judge the performance of both the methods Spearman’s Rank Correlation Coefficient was calculated and was observed to be within acceptable levels lending an index of robustness of the optimal choices of the strategies advocated by the MCDM methodologies adopted in the present case study.

Experimental and Theoretical Analysis of the Spray Characteristics of a High-Pressure Common-Rail Injection System Fueled with Neat Biodiesel, Ethanol-Biodiesel Blends, and Neat Diesel Fuel

AbstractIn this study, the spray and atomization characteristics of neat biodiesel, ethanol-biodiesel blends (BDEs), and neat diesel in a high-pressure common-rail injection system were investigate...

Performance analysis and emissions profile of cottonseed oil biodiesel–ethanol blends in a CI engine

ABSTRACTBiodiesel is identified as a likely alternative fuel for Compression Ignition (CI) engines as it leads to an effective reduction in consumption of petroleum diesel, and of engine exhaust emissions. In the current study, the effects of preheating of intake air on performance, emissions and combustion behavior have been studied for various compositions of cottonseed oil biodiesel–ethanol blends in a compression ignition engine. The characteristics were compared for intake air temperatures of 30°C and 80°C, respectively. An increase in the air intake temperature caused variations in the ignition delay period of the biodiesel–ethanol blend by improving the vaporization characteristic of ethanol, and provides a better combustion. It was found experimentally that the carbon monoxide (CO) as well as the unburned hydrocarbon (HC) emissions decreased with an increase in the preheat temperature, and were found to be slightly lower than those of biodiesel-fueled CI engines. An increase in the relative amount of ethanol blended with the biodiesel was also found to decrease CO and HC emissions. However, in comparison with biodiesel fuel, the ethanol–biodiesel blends resulted in higher emissions of oxides of nitrogen (NOx).

A comparative study of co-combustion process of diesel-ethanol and biodiesel-ethanol blends in the direct injection diesel engine

Abstract This paper presents the results of a comparative analysis of co-combustion of diesel and biodiesel fuels with hydrated ethanol. The engine tests were conducted for an on-cylinder natural aspirated compression ignition engine operated at a constant rotational speed of 1500 rpm. Experimental investigations were also conducted to evaluate the effects of using hydrated ethanol as additives to diesel or biodiesel fuels to enhance performance, emission and combustion characteristics of direct injection diesel engines. The test engine powered by a diesel-ethanol blend (DE) was compared to a biodiesel-ethanol (BE) blend, characterized by higher values of IMEP and ITE. In the case of the DE blend, the highest ITE value was obtained for 35% of the ethanol fraction (35%). As for the BE blend, similar ITE values (31%) were obtained over the entire range of the ethanol fuel fraction in the blend. In the case of pure B100 or D100 the ignition delay achieves near the same value equal to 17 deg. The lower unrepeatability of engine cycle obtained for the BE blend combustion did not exceed 10%. The highest NO x emissions were obtained for the DE blend with 30% of the EF fraction (5.5 g/kW h). Emissions of THC and NO x increase up to 35% of the EF fraction in blend.

Comparative investigation of emissions and combustion characteristics between ethanol-biodiesel-diesel blends and diesel fuel in a passenger car diesel engine

This study investigated the comparison of emissions and performance characteristics between ethanol-biodiesel-diesel blends and diesel fuel in a passenger car diesel engine. In order to analyse the effect of ethanol-biodiesel blends, the combustion and emission reduction characteristics of a four-cylinder diesel engine with common-rail direct injection system were investigated under the various injection and blended ratios. The experimental results showed that the combustion pressure of ethanol-biodiesel-diesel blended fuels slightly increased than that of convention diesel fuel at higher load condition, while the coefficient of variance of the combustion pressure (COVimep) showed almost the similar values. Under low-load conditions, the effects of ethanol-biodiesel blending to conventional diesel fuel on exhaust emissions showed that brake specific CO emission (BS-CO) and BS-HC emissions remarkably increased while BS-NOx emissions decreased as ethanol blending ratio increased. Under high load conditions, BS-CO, BS-HC and BS-NOx emissions slightly increased as ethanol blending ratio increased. On the other hand, the BS-Soot emissions were reduced by more than 50% in all conditions. [Received: October 16, 2015; Accepted: June 8, 2016]

Comparative investigation of emissions and combustion characteristics between ethanol-biodiesel-diesel blends and diesel fuel in a passenger car diesel engine

This study investigated the comparison of emissions and performance characteristics between ethanol-biodiesel-diesel blends and diesel fuel in a passenger car diesel engine. In order to analyse the effect of ethanol-biodiesel blends, the combustion and emission reduction characteristics of a four-cylinder diesel engine with common-rail direct injection system were investigated under the various injection and blended ratios. The experimental results showed that the combustion pressure of ethanol-biodiesel-diesel blended fuels slightly increased than that of convention diesel fuel at higher load condition, while the coefficient of variance of the combustion pressure (COVimep) showed almost the similar values. Under low-load conditions, the effects of ethanol-biodiesel blending to conventional diesel fuel on exhaust emissions showed that brake specific CO emission (BS-CO) and BS-HC emissions remarkably increased while BS-NOx emissions decreased as ethanol blending ratio increased. Under high load conditions, BS-CO, BS-HC and BS-NOx emissions slightly increased as ethanol blending ratio increased. On the other hand, the BS-Soot emissions were reduced by more than 50% in all conditions. [Received: October 16, 2015; Accepted: June 8, 2016]

Emission analysis of the effect of carbon nanowires in biodiesel–ethanol blends

ABSTRACTThe present work is dedicated to study of diesel–biodiesel–ethanol blends in a diesel engine using addition of various concentrations of carbon nanowires. Algae oil from microalgae has the potential to become a sustainable fuel source as biodiesel. The Neochloris oleoabundans algal oil was extracted by mechanical extraction method. The transesterification reaction of algal oil with methanol and base catalyst was used for the production of biodiesel. Experimental investigation results were studied for various parameters, such as exhaust emission of carbon monoxide, hydrocarbon, oxides of nitrogen gases, smoke, and carbon dioxide.

Characteristics analysis of carbon nanowires in diesel: Neochloris oleoabundans algae oil biodiesel–ethanol blends in a CI engine

ABSTRACTThe present work is dedicated to the study of diesel–biodiesel–ethanol blends in a diesel engine using carbon nanowires additives of various concentrations. Algae oil from microalgae has the possibility of becoming a sustainable fuel source as biodiesel. The Neochloris oleoabundans algal oil was extracted by the mechanical extraction method. The transesterification reaction of algal oil with methanol and base catalyst was used for the production of biodiesel. Experimental investigation results were studied for various parameters such as exhaust emission of carbon monoxide, hydrocarbon, oxides of nitrogen gases, and smoke.

Effect of nano additives (titanium and zirconium oxides) and diethyl ether on biodiesel-ethanol fuelled CI engine

The present work is dedicated to the comparative experimental study of biodiesel-ethanol blends in a compression ignition engine using TiO2 (Titanium oxide) nanoparticle, ZrO2 (Zirconium oxide) nanoparticle and DEE (Diethyl ether) additives. The test fuels used are a blend of biodiesel (80%) -ethanol (20%) (denoted as BE), a blend of BE with 25 ppm Titanium oxide nanoparticle (denoted as BE-Ti), a blend of BE with 25 ppm Zirconium oxide nanoparticle (denoted as BE-Zr) and a blend of BE with 50 ml Diethyl ether (denoted as BE-DEE). Addition of nanoparticles increases the oxidation rate, reduces the light-off temperature and creates large contact surface area with the base fuel thereby enhancing the combustion with minimal emissions. Experimental results shown that addition of Titanium nanoparticles increased NOx, HC and smoke with lowered BSFC and CO. Whereas addition of Zirconium nanoparticles increases BSFC and HC emissions with lowered CO, CO2 and smoke emissions in comparison with BE blends. DEE addition to BE blends improved the heat release rate and increased HC, CO emissions were observed with lowered BSFC, NOx and smoke. Simultaneous reduction of NOx and smoke indicates the effect of DEE on Low temperature combustion (LTC).

Study on use of biodiesel ethanol blend as a substitute in diesel engine

Alcohol in diesel engines can be used by two methods, one through fumigating alcohol in the combustion chamber using a carburetor and second is using alcohol and biodiesel blends. Blending of ethanol with biodiesel is easier. However, blending of ethanol is limited by proof level of ethanol; phase separation of ethanol-biodiesel blend occurs. This problem of phase separation should be solved by using certain surfactant like 1-butanol ethyl acetate etc. The substitute fuel of anhydrous and aqueous ethanol with biodiesel was prepared using ethyl acetate as surfactant and their stability at room temperature was observed.A Compression Ignition engine having rated power of 3.74 kW at 1500 rpm was tested on three samples of ethanol- ethyl acetate- biodiesel substitute fuels using 2000 proof ethanol containing 10 to 20 per cent ethanol with biodiesel and ethyl acetate. The performance of engine in respect of brake power, fuel consumption and brake fuel consumption, and emission of O2, CO2, NO and NO2 was evaluated to determine compatibility of substitute fuel as fuel for C.I. engine. The results obtained that all the three selected substitute fuel, viz. 2000-10/0/90, 2000-15/5/80 and 2000-20/10/70, had similar power producing capabilities, slightly higher fuel consumption, and lower exhaust emission as those of biodiesel fuel alone. Based on the study use of 2000- 20/10/70 ethanol –ethyl acetate –biodiesel substitute fuel recommended for fuel use in Compression Ignition engines. This substitute fuel may replace 30 per cent biodiesel with user emissions.

Experimental study of the performance and emission of diesel engine fueled with blends of diesel–ethanol as an alternative fuel

Evaluation of performance and emission was performed on a 3.7-kW, single-cylinder, four-stroke variable compression ratio diesel engine at a rated speed of 1500 rpm. The load ranges (0–0.7 kW, 1.2–2.3 kW, and 2.8–3.5 kW) are indicated as low, medium, and high loads respectively. Different blends of diesel and ethanol were prepared for the study on a volume/volume basis. The blends containing 5%, 10%, 15%, and 20% ethanol were fuel D95E5B0, D90E10B0, D70E15B15, and D60E20B20 respectively. Diesel–ethanol blends were D95E5B0 and D90E10B0, whereas diesel–ethanol–biodiesel blends were D70E15B15 and D60E20B20. The outcomes of the study showed that the brake thermal efficiency slightly decreased with increase in ethanol, the brake-specific fuel consumption increased with increase in ethanol, and the exhaust gas temperature increased for higher load and higher ethanol content in the blend. Oxides of nitrogen, carbon dioxide, hydrocarbon, and carbon monoxide decreased while smoke reduced drastically with a higher percentage of ethanol in the blend.