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The objective of this study designed in three steps is to evaluate the optimization of tribological performance in the elevated temperature of TiC reinforced A356 matrix composites, produced by mechanical alloying (MA), using the dragonfly algorithm (DA). In the first step, an experimental design is created to formulate the problem as an optimization problem with the help of regression modeling, and wear tests by adding a temperature module according to ASTM G99-05 standards are performed at various reinforced rates, operating temperatures, and loads. In the second step, regression models are fitted to the experimental results. In the third step, the dragonfly algorithm (DA) – one of the recent nature inspired metaheuristic optimization algorithms – has been adapted to optimize the formulated problem. The results of DA indicate that the optimum factor levels for the reinforced rate, operating temperature, and load are determined as 7%, 10°C, and 20 N respectively to optimize the responses, namely weight loss, wear rate, and friction coefficient.

Vegetable oil based microemulsion blends have received increased attention due to its free major drawback like chemicals, catalysts and process heat of transesterification compared to biodiesel. However, the lower cetane number (CN) of a vegetable oil based microemulsion blends prevents its using in diesel engines because of poorer self-ignitability. This study focused on the effect of 2-ethylhexyl nitrate (EHN) (cetane improver) addition on fuel properties, and engine performance and exhaust emission characteristics of diesel engine fueled with microemulsion blends. EHN was added at 500, 1000 and 2000 ppm concentration to diesel (D) (70 vol.%), sunflower oil (S) (20 vol.%) and n-butanol (B) (D70S20B10) or 1-pentanol (P) (10 vol.%) (D70S20P10) microemulsion blends to study its effect. Microemulsion blends with EHN were tested on a turbocharged direct injection (TDI) diesel engine at fixed engine speed (2200 rpm) and five different engine loads. The addition of EHN to microemulsion blends had positive effect on CN without causing any significant negative effect on other fuel properties of microemulsion blends. Engine performance test results showed that microemulsion blends with EHN had little effect on brake power and brake mean effective pressure (BMEP). Brake specific fuel consumption (BSFC) values reduced with increase of EHN concentration in the microemulsion blends in the range of 2.49–8.17%. Addition of EHN to microemulsion blends produced lower mean oxides of nitrogen (NO x ) in the range of 0.26–5.26%. D70S20B10 with 2000 ppm EHN has the best effects on the reduction of NO x emissions. However, carbon monoxide (CO) emissions increased in the range of 7.16–23.46% with increased presence of EHN concentration in microemulsion blends. Different trend in hydrocarbon (HC) emissions for D70S20B10 and D70S20P10 with EHN were observed.

Biodiesel and their blends with diesel have long been used as alternative fuels in diesel engines. In particular, B20 is recommended in most studies since it reduces the exhaust emissions and provides satisfactory engine torque close to diesel fuel. On the other hand, low cetane number of biodiesel leads to higher oxides of nitrogene (NOx) emission when compared to those of the diesel fuel. Formation of NOx emissions has a strong correlation with cetane number of fuels, which increases with the reduction of the cetane number. The current paper focuses on finding the optimum 2-ethylhexyl nitrate (EHN) (cetane improver) concentration and the engine speed for 20 vol% canola oil methyl ester and 80 vol% diesel fuel blend (B20). For that reason, experimental design is created and the experiments have been done on TDI diesel engine at full load and different engine speed conditions to be able to model the problem as an optimization problem by means of the regression modelling. Accordingly, the developed model in consequence of the test results of the engine is optimized via the grey wolf optimizer (GWO) algorithm taking into account of engine performance and emission parameters viz. brake torque, brake power, brake specific fuel consumption (BSFC), brake thermal efficiency (BTE), NOx, and carbon dioxide (CO2), to identify the rate of concentration of EHN in B20 and engine speed. Finally, confirmation tests were employed to compare the output values of the concentration that were identified through the GWO algorithm, and further statistical analyses indicate the consistency between the real experimental results and the results obtained through the GWO algorithm. The optimum EHN concentration and engine speed was determined as 743 mg/L and 3221 rpm respectively. Test results of engine performance indicated that brake power and BSFC of optimum blend at 3221 rpm decreased while brake torque and BTE increased in comparison with those of B20 without EHN. CO2 and NOx exhaust emissions decreased as 11.19% and 4.63% respectively.

Summary Alcohols extensively used in internal combustion engines are important renewable and sustainable energy resources from environmental and economical perspectives. Besides, bio production of alcohols decreases consumption of fossil-based fuels. Although there are many studies with regards to the use of lower alcohols such as methanol and ethanol in internal combustion engines, there are a limited number of investigations with higher alcohols. Higher alcohols such as propanol, n-butanol, and 1-pentanol are part of the next generation of biofuels, given they provide better fuel properties than lower alcohols. Biodiesel–higher alcohol blends can be used in diesel engines without any engine modification but need to be tested under various engine conditions with long periods in order to evaluate their impacts on engine performance and environmental pollutants. The objective of this study was to evaluate the effect of using propanol, n-butanol, and 1-pentanol in waste oil methyl ester (B100) on engine performance and exhaust emissions of a diesel engine running at different loads (0, 3, 6, and 9 kW) with a fixed engine speed (1800 rpm). Test fuel blends were prepared by adding propanol, n-butanol, and 1-pentanol (10 vol.%) into waste oil methyl ester to achieve blends of B90Pr10, B90nB10, and B90Pn10, respectively. According to engine performance and exhaust emissions results, the addition of propanol, n-butanol, and 1-pentanol to B100 had the effect of increasing brake specific fuel consumption and exhaust gas temperatures. The brake thermal efficiency (BTE) decreased for B90Pr10 and B90nB10, while B90Pn10 showed a slight increase in BTE as compared with B100. When compared with B100, B90Pr10, B90nB10, and B90Pn10 decreased carbon monoxide emissions at lower loads while it increased slightly at 9 kW load. The decrement in oxides of nitrogen emission was observed at whole loads for B90Pr10, B90nB10, and B90Pn10 compared with B100. When considering all loads, B90Pn10 presented the best mean hydrocarbon emission with a reduction of 45.41%. Copyright © 2016 John Wiley & Sons, Ltd.

The rule of thumb in literature is that 20% of biodiesel is the most acceptable blend ratio in alternative fuel blends. This work focuses on in-depth mathematical optimization analyses of ternary blends of diesel–butanol–vegetable oil (cotton oil), based on engine operating parameters using RSM (response surface methodology). It is critical to achieve the maximum power and torque for customers while keeping the emissions low enough due to government regulations and certifications. Thus, three optimization studies were conducted at 2200 rpm, which corresponds to the maximum brake torque, and engine emissions were fixed at a maximum possible value based on emission standards, for all three studies. In order to understand the impact of other engine parameters on the blend ratio, as well, various combinations of BTE (brake thermal efficiency), maximum brake power, maximum brake torque, BSFC (brake specific fuel consumption) and BMEP (brake mean effective pressure) were fixed, which correspond to Opt-1 (optimization 1) (BTE and exhaust emissions), optimization 2 (BTE, brake power and exhaust emissions), and optimization 3 (BTE, brake power, brake torque, BSFC, BMEP and exhaust emissions). Optimization studies used experimentally determined emissions and performance data of a diesel engine based on 7 different concentrations of diesel–butanol–cotton oil blends. Optimum values of the blends corresponding to the optimization studies were mathematically determined as Opt-1 (optimization 1) (61.7 vol.% diesel, 34.75 vol.% butanol, 3.55 vol.% cotton oil), Opt-2 (optimization 2) (64.5 vol.% diesel, 28.7 vol.% butanol, 6.8 vol.% cotton oil), and Opt-3 (optimization 3) (65.5 vol.% diesel, 23.1 vol.% butanol, 11.4 vol.% cotton oil). When compared to diesel, BSFCs of Opt-1, Opt-2 and Opt-3 blends at 2200 rpm increased 41.57, 33.87 and 24.53%, respectively. In terms of basic exhaust gas emissions, optimum fuel blends decreased NO x (oxides of nitrogen), CO (carbon monoxide) and HC (hydrocarbon) emissions as compared to diesel.

n-Butanol is a promising next generation alternative fuel for stabilizing diesel fuel–vegetable oil blends at low temperatures. In this study, the effects of higher n-butanol contents in diesel fuel–vegetable oil blends in a diesel engine were investigated. Ternary blends of diesel fuel (D)–cotton oil (CtO)–n-butanol (nB) as percentages (vol.%) of 60%D–10%CtO–30%nB (TB1), 50%D–30%CtO–20%nB (TB2), 30%D–30%CtO–40%nB (TB3), 30%D–10%CtO–60%nB (TB4) and 20%D–20%CtO–60%nB (TB5) were selected in the soluble area of the ternary phase diagram for low temperature (−15 °C) operability. The tests were conducted employing each of the above ternary blends and diesel fuel, with the engine operating at full load and eight different engine speeds between 1800 and 4400 rpm. Increasing presence of n-butanol in the blends improved density, kinematic viscosity and cold filter plugging point (CFPP), while deteriorated cetane number (CN) and heating value of the ternary blends. Experimental test results of ternary blends showed that average brake torque, brake power, brake thermal efficiency (BTE) and exhaust gas temperature decreased, while brake specific fuel consumption (BSFC) increased with increasing presence of n-butanol in the blends. Addition of n-butanol to diesel fuel–vegetable oil blends increased oxides of nitrogen (NO and NO 2 ) formations, while drastically decreasing formation of carbon monoxide (CO) and hydrocarbon (HC) emissions. TB4 and TB5, which have the highest ratio of n-butanol, are promising candidate for decreasing CO and HC emissions at the expense of increasing BSFC.

In this study, n-butanol (nB) was used as the common solvent and crude canola (Cn), soybean (Sb), sunflower (Sf), corn (Cr), olive (Ol), and hazelnut oil (Hn) as the vegetable oil components were used for making microemulsification of diesel fuel (D)-vegetable oil blends. The blend ratios of 70% vol. D, 20% vol. vegetable oil and 10% vol. nB were determined to increase concentration of biofuels in ternary blends. Six different ternary blends were prepared via the splash blending method. Engine performance tests of the ternary blends were carried out on a four-cylinder, four-cycle turbocharged direct-injection diesel engine at full load with various engine speeds. Test fuels were kept stationary at ambient temperature and the long-term stabilities were observed at 60 days. There were not any phase separations in the ternary blends. Fuel properties of the test fuels were examined and determined to be in agreement with the fuel standards. According to engine performance test results of the ternary blends, brake torque, brake power, brake thermal efficiency (BTE), brake mean effective pressure (BMEP) and exhaust gas temperatures decreased while brake specific fuel consumption (BSFC) increased as compared to those of diesel fuel. In terms of basic exhaust gas emissions, ternary blends increased nitric oxide (NO) and carbon monoxide (CO) emissions while reducing hydrocarbon (HC) and carbon dioxide (CO2) emissions as compared to diesel.

Many studies declare that 20% biodiesel is the optimum concentration for biodiesel–diesel fuel blends to improve performance. The present work focuses on finding diesel fuel, n-butanol, and cotton oil optimum blend ratios for diesel engine applications by using the response surface method (RSM). Experimental test fuels were prepared by choosing 7 different concentrations, where phase decomposition did not occur in the phase diagram of −10 °C. Experiments were carried out at full load conditions and the constant speed (2200 rpm) of maximum brake torque to determine engine performance and emission parameters. According to the test results of the engine, optimization was done by using RSM considering engine performance and exhaust emissions parameters, to identify the rates of concentrations of components in the optimum blend of three. Confirmation tests were employed to compare the output values of concentrations that were identified by optimization. The real experiment results and the R2 actual values that show the relation between the outputs from the optimizations and real experiments were determined in high accordance. The optimum component concentration was determined as 65.5 vol.% diesel, 23.1 vol.% n-butanol and 11.4 vol.% cotton oil (DnBC). According to engine performance tests brake torque, brake power, BTE and BMEP of DnBC decreased while BSFC increased compared to those of diesel fuel. NOx, CO and HC emissions of DnBC drastically decreased as 11.33%, 45.17% and 81.45%, respectively.

In this study, the effect of the antioxidant additives on the oxidation stability of biodiesel and the exhaust emissions of a diesel engine has been studied. Biodiesel used in this study was produced via transesterification process from canola oil, and was blended with diesel fuel 20% by volume (B20). Antioxidant additives butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), tert-butylhydroquinone (TBHQ) and 2-ethylhexyl nitrate (EHN) were individually dissolved at concentrations of 0, 500, 750 and 1000 ppm by weight in B20 fuel blend for experiments. The test results of oxidation stability showed that the effectiveness of the antioxidants was in the order of TBHQ > BHA > BHT > EHN. According to exhaust emissions test results, antioxidant additives had quite effects on oxides of nitrogen (NOx), carbon monoxide (CO) and hydrocarbon (HC) emissions of diesel engine running on biodiesel. A 1000 ppm concentration of EHN additive was optimal as NOx levels were substantially reduced in the whole engine speed in comparison with B20 fuel.

The aim of the present study was to evaluate the effect of using n -butanol in vegetable oil–diesel fuel blends on engine performance and exhaust emissions of a direct injection diesel engine operating at full load (100% throttle conditions) with different engine speeds without any engine modification. Neat canola-hazelnut-cottonseed oil (CHC) and neat sunflower–corn–soybean oil (SCS) blends were prepared as equal vol.% by splash blending method. Diesel fuel (70 vol.%) and n -butanol (10 vol.%) are added into CHC and SCS blends (denoted as DCHCnB and DSCSnB, respectively), simultaneously. Basic fuel properties of DCHCnB and DSCSnB are similar to those of diesel fuel. According to engine performance and exhaust emission test results of DCHCnB and DSCSnB, average values of brake torque (−6.08% and −6.67%), brake power (−4.12% and −4.59%), brake thermal efficiency (BTE) (−10.80% and −11.66%), exhaust gas temperature (−15.11% and −14.99%), carbon dioxide (CO 2 ) (−1.12% and −2.30%) and hydrocarbon (HC) (−36.71% and −32.28%) are lower, while brake specific fuel consumption (BSFC) (18.43% and 19.58%), oxides of nitrogen (NO x ) (27.27% and 30.36%) and carbon monoxide (CO) (41.57% and 26.89%) are higher than those of diesel fuel.

An experimental investigation has been carried out to analyze the effect of antioxidants on engine performance and exhaust emissions of a diesel engine fueled with B20 (20 vol.% canola oil methyl ester and 80 vol.% diesel fuel blend). The four synthetic antioxidants, butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), tert-butylhydroquinone (TBHQ) and 2-ethylhexyl nitrate (EHN), were tested on a Land Rover turbocharged direct injection (TDI) 110 type diesel engine with water cooled, 4-cycl and 4-cylinder. The addition of antioxidants to B20 did not cause any negative effect on basic fuel properties of B20. According to engine performance test results, brake specific fuel consumption (BSFC) of B20 with antioxidants decreased compared to those of B20 without antioxidants. A 1000 ppm concentration of TBHQ was optimal as BSFC values were considerably reduced (10.19%) in the whole engine speeds when compared to B20. EHN antioxidant with B20 presented the best mean oxides of nitrogen (NOx) with a reduction of 4.63%. However, formation of carbon monoxide (CO) emissions has been increased with addition of each of the antioxidants to B20.

This study focused on the effect of temperature and component concentration on phase stability of diesel–cotton oil– n -butanol ternary blends. Titration method was performed for plotting phase diagrams at different temperatures (−10, −5, 0, 5 and room temperature). Ternary blend of 70% diesel fuel, 20% cotton oil, 10% n -butanol by volume (DCtOnB), which was prepared by the splash-blending method, obtained from titration values at −10 °C temperature was selected for the engine performance and exhaust emission tests. Engine performance test results of DCtOnB showed that average values of brake torque (2.6%), brake power (1.6%), brake thermal efficiency (BTE) (31.2%), brake mean effective pressure (BMEP) (2.3%) and exhaust gas temperature (3.6%) are lower, while brake specific fuel consumption (BSFC) (34.1%) is higher than those of diesel fuel. As for the emissions of the DCtOnB, it was found that carbon monoxide (CO) and carbon dioxide (CO 2 ) emissions reduced significantly at low engine speeds, whereas oxides of nitrogen (NO x ) and hydrocarbon (HC) emissions increased, when compared to those of diesel fuel. Taking these facts into account, a blend of 70% diesel fuel, 20% cotton oil and 10% n -butanol was found the most suitable ratio for low temperature behavior due to the satisfactory fuel properties and reduced exhaust emissions.

An experimental investigation was conducted to evaluate the suitability of hazelnut oil methyl ester (HOME) for engine performance and exhaust emissions responses of a turbocharged direct injection (TDI) diesel engine. HOME was tested at full load with various engine speeds by changing fuel injection timing (12, 15, and 18 deg CA) in a TDI diesel engine. Response surface methodology (RSM) and least-squares support vector machine (LSSVM) were used for modeling the relations between the engine performance and exhaust emission parameters, which are the measured responses and factors such as fuel injection timing (t) and engine speed (n) parameters as the controllable input variables. For this purpose, RSM and LSSVM models from experimental results were constructed for each response, namely, brake power, brake-specific fuel consumption (BSFC), brake thermal efficiency (BTE), exhaust gas temperature (EGT), oxides of nitrogen (NOx), carbon dioxide (CO2), carbon monoxide (CO), and smoke opacity (N), which are affected by the factors t and n. The results of RSM and LSSVM were compared with the observed experimental results. These results showed that RSM and LSSVM were effective modeling methods with high accuracy for these types of cases. Also, the prediction performance of LSSVM was slightly better than that of RSM.

This paper presents the effect of fuel injection advance on engine performance and exhaust emission parameters using a diesel engine running on canola oil methyl ester (COME). COME was produced and...

In this study, usage of methyl ester obtained from waste cooking oil (WCOME), hazelnut oil (HOME), and canola oil (COME) is examined as an experimental material. A reactor was designed and installed for production of methyl ester from these kinds of oil. Physical and chemical properties of methyl esters were determined in the laboratory. The methyl esters were tested in a turbocharged diesel engine with four cylinders and direct injection. The results were compared with No. 2 diesel fuel. The comparison of emission test results of the biodiesel fuels produced in this study with No. 2 diesel fuel yielded that the obtained measurements of CO, CO2, NOx, smoke density, and exhaust temperatures of biodiesel fuels were less than those of No. 2 diesel fuel.

Karaoğlan, Aslan Deniz (Balikesir Author), The objective of this study was to investigate the effect of fuel injection timing and engine speed on engine performance and exhaust emission parameters using a diesel engine running on canola oil methyl ester (COME). COME was produced by means of the transesterification method and tested at full load with various engine speeds by changing fuel injection timing (12, 15, and 18 degrees CA) in a turbocharged direct injection (TDI) diesel engine. The experiments were designed using response surface methodology (RSM), which is one of the well-known design of experiment technique for predicting the responses engine performance and exhaust emission parameters from a second order polynomial equation obtained by modeling the relation between fuel injection timing (t) and engine speed (n) parameters. By using the second order full quadratic RSM models obtained from experimental results, responses brake power, brake torque, brake mean effective pressure, brake specific fuel consumption, brake thermal efficiency, exhaust gas temperature, oxygen (O-2), oxides of nitrogen (NOx), carbon dioxide (CO2), carbon monoxide (CO), and light absorption coefficient (K) affected from factors t and n were able to be predicted by 95% confidence interval.