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Öğe Alternative fuel production from waste plastics and their usability in light duty diesel engine: Combustion, energy, and environmental analysis(Elsevier Ltd, 2023) Mohan, Revu Krishn; Sarojini, Jajimoggala; Rajak, Upendra; Verma, Tikendra Nath; Ağbulut, ÜmitGreen biofuels have long been touted as a potential solution to society's reliance on fossil fuels and pollution emission problems. Commercially available renewable fuels like waste plastics oil alternative (P) made from waste plastic oil could take the place of fossil fuels, especially in diesel engines. Binary alternatives and diesel blends that partially replace diesel can be used in diesel engines without requiring major modifications. A four-stroke diesel engine used in the experiment was fed waste plastics oil alternative (up to 40% volumetric content), and diesel (D) mixes. Each binary blend is stabilised by a volumetric concentration and is composed of varying oil proportions. The investigations, therefore, relate partial diesel replacements to assessments of engine performance and mix combustion under various load conditions (25–100%), speeds (1200–1800 rpm), and compression ratios (15–19). Results showed that alternative-diesel mixtures up to 40% can still operate reliably. Thermal efficiency was somewhat lower than for diesel which was 100%. The experiment revealed higher fuel use, smoke, and NO emissions. The conclusion of the present research states that waste product oils can compete with fossil fuels in terms of engine performance, combustion, and emission characteristics when utilized in light-duty engines. © 2022 Elsevier LtdÖğe Collective influence and optimization of 1-hexanol, fuel injection timing, and EGR to control toxic emissions from a light-duty agricultural diesel engine fueled with diesel/waste cooking oil methyl ester blends(Institution of Chemical Engineers, 2023) De Poures, Melvin Victor; Dillikannan, Damodharan; Kaliyaperumal, Gopal; Thanikodi, Sathish; Ağbulut, Ümit; Hoang, Anh Tuan; Mahmoud, Z.This study attempts to utilize a ternary blend comprising diesel, biodiesel, and 1-hexanol in a direct injection (DI) diesel engine. A response surface methodology (RSM) based optimization with the full factorial experimental design was used to optimize the fuel injection timing and exhaust gas recirculation (EGR) with an objective to maximize the performance of the engine with minimum emissions. Three injection timings and three EGR rates were used. Multiple regression models developed using RSM for the responses were found to be statistically significant. Interactive effects between injection timing and EGR on responses for the blends were studied. From a desirability approach, a HX20 blend (diesel 50 v/v% + biodiesel 30 v/v% + 1-hexanol 20 v/v%) injected at lesser fuel injection timing and EGR rate delivered optimum emission and performance characteristics. Confirmatory tests validated the models to be adequate. With reference to diesel, at optimum conditions, there was a significant reduction in nitrogen oxides (NOx) emission with a marginal increase in smoke, hydrocarbon (HC) and carbon monoxide (CO) emissions. Also, it was found that there was minimal loss in brake thermal efficiency (BTE) of the engine. With respect to waste cooking oil methyl ester operation, the blend reduced nitrogen oxides (NOx), smoke, carbon monoxide (CO) and hydrocarbon (HC) emissions significantly with marginal loss in BTE. © 2023 The Institution of Chemical EngineersÖğe Combustion, performance, vibration and noise characteristics of cottonseed methyl ester-diesel blends fuelled engine(Taylor & Francis Ltd, 2019) Sarıdemir, Suat; Ağbulut, ÜmitAn experimental study was conducted to evaluate the impacts of using cottonseed methyl ester as an additive into neat diesel fuel on the combustion, performance, vibration and noise characteristics of a single-cylinder, direct injection diesel engine at a constant engine speed (1500 rpm) and under different engine loads (2.5, 5, 7.5 and 10 Nm). B-10, B-20 and B-50 fuel blends were prepared as the working fuels and compared to B-0 reference fuel (neat diesel fuel) in the study. The results indicated that the lowest average vibration value was also obtained in B-20 type fuel. It was observed that cottonseed methyl ester due to the high oxygen content improved the quality of combustion process. Additionally, the high viscosity value of the used biodiesel increased the ignition delay by adversely affecting the atomisation, evaporation and mixing ratio of the fuels. On the other hand, BSFC increased with the increment of the biodiesel ratio in the blends i.e. the maximum BSFC was observed in B50 fuel type. In all fuel blends except for B-50 type, IPmax values were achieved higher than B-0 for each engine load. In conclusion, the experimental results clearly reported that the presence of cottonseed methyl ester in the blends can alternatively be substituted for the neat diesel fuel without any modifications in diesel engines.Öğe A comprehensive review on the usage of the nano-sized particles along with diesel/biofuel blends and their impacts on engine behaviors(Elsevier Ltd, 2023) Gad, Mohammed Sayed; Ağbulut, Ümit; Afzal, Asif; Panchal, H.; Jayaraj, S.; Qasem, N.A.A.; El-Shafay, A. S.Global warming, climate change, air pollution, and harmful exhaust emissions for human health are highly associated with the burning of petroleum fuels at a huge level. In the beginning, biodiesel fuels have been introduced as a promising alternative fuel to mitigate these problems. However, poor atomization, low energy content, high viscosity, and density of biodiesels are the main obstacles to the frequent usage of biodiesel fuels in diesel engines. That is because biodiesel fuels in CI engines have generally resulted in higher fuel consumption, lower thermal efficiency, and higher NOx emission. On the other hand, most fuel researchers recently announced that the addition of nanoparticles in biodiesel blends has led to making biodiesels attractive again by significantly improving their poor biodiesel properties such as thermophysical properties, calorific value, heat transfer rate, evaporation rate, etc. From this point of view, many published papers in the area demonstrated that the addition of nanoparticles in biodiesel blended fuels has simultaneously provided fewer exhaust emissions, better performance, and combustion characteristics thanks to the high catalyst effect of nanoparticles. In the conclusion, the present review paper clearly announced that the addition of nanoparticles is a very strong way to re-improving the worsened engine combustion, performance, and emission characteristics of biodiesel-diesel blends. © 2023 Elsevier LtdÖğe Current practices, potentials, challenges, future opportunities, environmental and economic assumptions for Türkiye's clean and sustainable energy policy: A comprehensive assessment(Elsevier Ltd, 2023) Ağbulut, Ümit; Yıldız, Gökhan; Bakır, H.; Polat, Fikret; Biçen, Yunus; Ergün, Adem; Gürel, Ali EtemIn today's world, most countries including Türkiye have met their electricity demand at a dominant rate by burning fossil-based fuels in thermal power plants. However, fossil-fuel reserves have been rapidly depleted, resulting in high volatility in these fuels’ markets, as well as alarming environmental, and economic problems for the governments. In recent years, many governments have started to face these problems and have rapidly transitioned to renewable and alternative carbon-free energy sources in their electricity production variety. However, these belated steps have failed to mitigate the increment in global greenhouse gas emissions against the rapid growth of population and energy demand. In recent years, Türkiye has put a noteworthy challenge to mitigate its dominant use of fossil fuels, reducing its energy dependence, sustaining its economic development, and mitigating the carbon footprint. From this point of view, it is witnessed that many power plants have been established, many of them are currently under construction, especially to produce more electricity in a sustainable way. Accordingly, the present study aims to comprehensively discuss Türkiye's energy production policy, energy potential and reserves, challenges, future opportunities, and the impacts of the energy sector on the economic and environmental issues for the country. In this framework, it is well-noticed that the country's future energy production policy has been reasonably changed in order to achieve positive economic and environmental outcomes in the medium and long term. © 2023 Elsevier LtdÖğe Energetic, exergetic, and thermoeconomic analyses of different nanoparticles-added lubricants in a heat pump water heater(Elsevier, 2022) Yıldız, Gökhan; Ağbulut, Ümit; Gürel, Ali Etem; Ergün, Alper; Afzal, Asif; Saleel, C. AhamedThe heat pumps are frequently used in domestic and industrial applications for hot water supply. The present paper aims to thermodynamically investigate the impacts of the nanoparticle-addition into the lubricants on the energetic, exergetic, and thermoeconomic aspects of a heat pump. In the experiments, air to the water heat pump is separately charged with various metal oxide-based nanoparticles (Al2O3, CuO, and TiO2)-added oils at a constant mass fraction of 0.5%. Polyolester (POE) and 134a are used as a lubricant, and refrigerant, respectively. The mass flow rates of the water passed through the condenser are varied from 10 to 25 g/s with an interval of 5 g/s. In the results, it is observed that the thermal conductivity value noteworthy increases with the presence of nanoparticles in POE. The highest increment in thermal conductivity is found to be 39% for POE + CuO in comparison with that of pure POE. Furthermore, with nanoparticles addition, it is noticed that the COP value generally improves, and the highest improvement for COP value is noticed to be 8% for POE + TiO2 nanolubricant at the mass flow of 25 g/s. Furthermore, exergy efficiency enhances by 3.6%, 1.8%, and 4.5% for POE + Al2O3, POE + CuO, and POE + TiO2, respectively. The lowest heating cost is calculated to be 3.465 c/kWh at 20 g/s flow rate for POE + Al2O3. In conclusion, this paper clearly reports that usage of nanoparticles along with lubricants is presenting better energetic, exergetic, and thermoeconomic results rather than the usage of lubricant alone in the heat pumps.Öğe Energy, exergy, sustainability and economic analysis of waste tire pyrolysis oil blends with different nanoparticle additives in spark ignition engine(Pergamon-Elsevier Science Ltd, 2022) Yaqoob, Haseeb; Teoh, Yew Heng; Sher, Farooq; Jamil, Muhammad Ahmad; Ali, Mubbashar; Ağbulut, Ümit; Salam, Hamza AhmadFossil fuels are the primary source of energy for most industries worldwide. However, its resources are finite and declining day by day, and toxic gases are released due to their consumption which causes global warming and problems with the health of the living. Therefore, any alternatives to fossil fuels or any additives added to the fuel needed to be found to minimize fuel consumption and the emission of harmful gases. In this study, a spark-ignition engine fuelled with blends of petrol with different concentrations of graphite nanoparticles, Fe2O3 nanoparticles, and tire pyrolysis oil (TPO) were used to conduct energy, exergy, economic, and sustainability analyses, and the obtained results were compared with neat petrol. The blends of petrol with 40 mg/L, 80 mg/L, and 120 mg/L of graphite nanoparticles & Fe2O3 nanoparticles, as well as 5% & 10% TPO, were used in a single-cylinder, four-stroke, air-cooled SI engine in this study. The experiments were conducted on various engine loads of 2 Nm to 10 Nm with an increment of 2 Nm at a constant speed of 3500 rpm. The maximum exergy and energy efficiencies were obtained 23.05% and 21.94% at a load of 8 Nm when the testengine fired with the P120FO blend, respectively. A maximum sustainability index of 1.3 for the P120FO blend was obtained. A minimum exhaust energy rate of 0.03241 kW was obtained for P120FO. A minimum exhaust exergy rate of 0.005849 kW was obtained for P90T10. Best results in energy efficiency, exergy efficiency, sustainability index, and economic analysis were obtained for the P120FO blend compared to neat petrol. Finally, it was concluded that the addition of nanoparticles in fossil fuel increases the engine's efficiency, decreases fuel consumption, and reduces the emission of harmful gases. (c) 2022 Elsevier Ltd. All rights reserved.Öğe An enhancement in diesel engine performance, combustion, and emission attributes fueled with Eichhornia crassipes oil and copper oxide nanoparticles at different injection pressures(Taylor & Francis Inc, 2022) Khan, Osama; Khan, Mohd Zaheen; Khan, Emran; Bhatt, Bhupendra Kumar; Afzal, Asif; Ağbulut, Ümit; Shaik, SaboorCurrent scenario of crude oil exhaustion and price rise has motivated researchers to opt and explore other forms of energy which are renewable and sustainable in nature. Waste plant oils have significant potential to become a viable alternative to petro-diesel fuel for transportation and manufacturing purposes. Esterification of unrefined waste oils has significantly addressed the issues mainly occurring due to highly viscous nature of the oil. This analysis aims to conduct a controlled study to examine the impact of injection pressure on the engine parameters amalgamated with copper (III) oxide composites as a nanofuel additive. Biofuel obtained from waste plants (Eichhornia Crassipes) is amalgamated with plain diesel in a 30:70 ratio and copper (III) oxide (Cu2O3) as nano-additive. It is essential to operate the engine over a wide range of injection pressures (180, 200, and 220 bar) for furnishing maximum efficiency when mixed with 90 ppm nano-additive volume fraction. The current analysis shows that the injection of nano-additives raises the injection pressure leads to enhanced engine combustion characteristics, including a maximum peak pressure and a faster heat release rate. At 220 bar, injection pressure with a 90-ppm volumetric fraction of nano-additives yielded superior results in comparison with its counterpart blends. The inclusion of nano-additives for increased injection pressures decreases emissions of hydrocarbon, oxides of nitrogen, and soot particles. Thus, biofuels engines benefit by enhanced injection pressure and decreased emission levels by successfully amalgamating copper (III) oxide as nano-additives. Combined effect of high pressure and nano-additive fuel furnishes a maximal progression of 3.5% in combustion efficacy and a 14% drop in BSEC with reduction of 14% in HC, 15% in NOx, and 15% in smoke.Öğe Environmental and economic assessment of a low energy consumption household refrigerator(Elsevier B.V., 2019) Gürel, Ali Etem; Ağbulut, Ümit; Ergün, Alper; Ceylan, İlhanEnergy consumption is the biggest obstacle in the economic growth of a country. In recent years, Turkey has imported around at the rate of three-quarters of its total energy demand. Upon the past 10-years running, Turkey paid nearly half a trillion dollars for its total energy bill. The big share of energy consumption has emerged from buildings. Therefore, energy savings have great importance, particularly in the buildings. A refrigerator is responsible for the most dominant electrical energy consumption rate with 32% in a house. Therefore, this paper proposes a novel household refrigerator design for reducing energy consumption. In the proposed design, the necessary air for the cooling process will be provided from outdoor ambient in appropriate weather condition. The compressor work will, thus, be decreased via this way, and contribute to a reduction in energy consumption. The results indicated that this system in 63 provinces can be effectively used between 1 and 4 months and help to reduce 36 million $ in Turkish electric energy bill with the use of only 1 year period. Additionally, a reduction of approximately 850,000 tons of CO2 annually in Turkey can be achieved by applying the proposed design in this study. Hereby, Turkey can contribute not only to be sustained economic growth but also to reduce harmful gas emissions arising from electricity generation methods in the country. © 2019 Karabuk UniversityÖğe Exergetic, exergoeconomic, and sustainability analyses of diesel-biodiesel fuel blends including synthesized graphene oxide nanoparticles(Elsevier Sci Ltd, 2022) Uysal, Cüneyt; Ağbulut, Ümit; Elibol, Erdem; Demirci, Tuna; Karagöz, Mustafa; Sarıdemir, SuatIn this study, graphene oxide nanoparticles were synthesized and added to 85 vol% diesel + 15 vol% biodiesel (D85B15) blend with amounts of 100 ppm, 500 ppm, and 1000 ppm to prepare D85B15GO100, D85B15GO500, and D85B15GO1000 blends, respectively. The prepared fuels were tested in a compression ignition diesel engine. The experiments were performed on various engine loads ranging from 3 Nm to 12 Nm with intervals of 3 Nm at fixed crankshaft speed of 2400 rpm. The results obtained from the experiments were used in the exergetic, exergoeconomic, and sustainability analyses of test engine. According to the results, D85B15GO100 had the highest exergy efficiency and sustainability index and the second-cheapest specific exergy cost of crankshaft work. As a result, at 12 Nm, the exergy efficiency, specific exergy cost of work produced by crankshaft, and sustainability index values of test engine were 25.82%, 75.82 $/GJ, 1.348 for D85B15, whereas these values were 27.05%, 77.52 $/GJ, 1.371 for D85B15GO100, respectively. Increase in graphene oxide nanoparticle content in the blend led to decrease in the exergy efficiency and sustainability index and increase in the specific exergy cost of crankshaft work. Finally, it can be concluded that D85B15GO100 is optimal fuel compared to the fuels tested in this study.Öğe Exergy, exergoeconomic, life cycle, and exergoenvironmental assessments for an engine fueled by diesel-ethanol blends with aluminum oxide and titanium dioxide additive nanoparticles(Elsevier Sci Ltd, 2022) Ağbulut, Ümit; Uysal, Cüneyt; Cavalcanti, Eduardo J. C.; Carvalho, Monica; Karagöz, Mustafa; Sarıdemir, SuatThis study develops energy, exergy, exergoeconomic, exergoenvironmental, and sustainability analyses for a compression ignition (CI) engine fueled with neat diesel (D100), 90 vol% neat diesel + 10 vol% ethanol (D90E10), D90E10 + 100 ppm Al(2)O(3 )nanoparticle (D90E10Al(2)O(3)), and D90E10 + 100 ppm TiO2 nanoparticle (D90E10TiO(2)). The experiments were performed on various engine loads (from 3 Nm to 12 Nm with 3 Nm increments) at a fixed crankshaft speed of 2400 rpm. D90E10Al(2)O(3) showed the best energy, exergy, exergoenvironmental, and sustainability results among all fuels. However, according to exergoeconomic analysis, the lowest cost of crankshaft work was obtained with D100, followed by D90E10Al(2)O(3). This means that D90E10Al(2)O(3) presented better exergoeconomic results than its base fuel D90E10 and D90E10TiO(2) but worse exergoeconomic results than D100. The addition of ethanol to D100 excessively increased the fuel cost. As a result, the crankshaft work cost flow rate is 0.7645 $/h for D100, 1.1123 $/h for D90E10, 1.1069 $/h for D90E10Al(2)O(3) and 1.1338 $/h for D90E10TiO(2). Similarly, the environmental impact rate of work is 250.8 mPt/h for D100, 264.2 mPt/h for D90E10, 245.6 mPt/h for D90E10Al(2)O(3 )and 248.7 mPt/h for D90E10TiO2. Increments in the engine load have led to increases in all environmental impact rates due to higher fuel consumption but caused a decrease in the environmental impact rate per exergy unit. In conclusion, it is well noticed that fuel blends with nanoparticles can be used as alternative fuels to their base fuels, but D100 (or an equivalent lower-cost fuel than D100) should be selected for cost-effectiveness purposes.Öğe Exergy, sustainability and performance analysis of ground source direct evaporative cooling system(Elsevier, 2022) Yıldız, Gökhan; Ergun, Alper; Gürel, Ali Etem; Ceylan, İlhan; Ağbulut, Ümit; Eser, Servet; Afzal, AsifA significant portion of global energy consumption is due to energy consumption in the buildings. Heating, cooling, and air conditioning systems have the largest share in this energy consumption. Evaporative cooling systems, which have the advantage of being economical, zero pollution, and easy maintenance are preferred to reduce energy consumption in buildings. These systems are used in many areas such as greenhouses, broiler houses, and warehouses. In this study, analyzes of exergy, sustainability, and cooling efficiency in four different situations of a ground source direct evaporative cooling system were made. The system was studied in four different cases. While the highest exergy efficiency was obtained in case 3 with 20.83%, the exergy efficiencies in other cases were obtained as 16.83%, 17.49%, and 18.36%, respectively. In addition, the highest specific exergy loss was determined as 100.51 J/kg in case 2, while it was calculated as 73.08 J/ kg, 80.23 J/kg, and 73.05 J/kg for the other cases, respectively. It is seen that the sustainability values are in parallel with the exergy efficiency when the evaporative cooling system is examined for four different cases. The sustainability values were determined as 1.20 for case 1, 1.21 for case 2, 1.26 for case 3, and 1.22 for case 4. It is determined that the exergy efficiency gives precise information about the usability and sustainability of the system when these situations are evaluated. The exergetic improvement potential (EIP) was determined as 0.061 for case 1, 0.082 for case 2, 0.063 for case 3, and 0.059 for case 4, respectively. Although the highest exergy efficiency is obtained in case 3, it has a higher recovery potential than case 1 and case 4. In addition, cooling efficiencies for four different cases were obtained as 33.70%, 34.81%, 41.69%, and 36.95%, respectively. The temperature differences between the room and ambient temperatures were determined as 1.45 degrees C, 1.21 degrees C, 1.6 degrees C, and 1.48 degrees C for each case, respectively.Öğe Experimental and numerical assessment of the rotary bed reactor for fuel-processing and evaluation of produced oil usability as fuel substitute(Elsevier, 2022) Gad, Mohammed Sayed; Ağbulut, Ümit; El-Shafay, A. S.; Panchal, Hitesh; Emara, Kareem; Al-Mdallal, Qasem M.; Afzal, AsifIn current work, waste tires recycling using pyrolysis was performed inside a rotary bed reactor without oxygen-producing oil, black carbon, and synthetic gas. In that respect, CFD analysis was applied using ANSYS software to design the reactor and test its material resistance to the temperature rise. Thermal and mechanical stresses were evaluated to find an acceptable reactor design. Pyrolysis of tires to oil was performed at a temperature of 420 degrees C. Tire and diesel oils blends of 5, 10, and 20% volume percentages were prepared for experimentation. Tire oil blends properties were close to crude diesel. Characteristics of combustion, performance and emissions of diesel engines that used tire oil blends were investigated compared to crude diesel. The thermal efficiency maximum decrease of TO20 was 21% in comparison to pure diesel. The maximum increases in CO, smoke, and HC emissions of TO20 were 35, 20, and 25% compared to diesel fuel, respectively. The highest decline in NOx emission of TO20 was 19% related to crude diesel fuel. Oil blends achieved the higher peak cylinder pressures about diesel fuel. In conclusion, lower volume percentages of up to 20% of tire and diesel oil blends are recommended to be used without any engine modifications.Öğe Experimental assessment of the influences of liquid-solid-gas fuel blends on DI-CI engine behaviors(Elsevier, 2022) Polat, Fikret; Yeşilyurt, Murat Kadir; Ağbulut, Ümit; Karagöz, Mustafa; Sarıdemir, SuatThis study aims to deeply investigate the effects of the boron nanoparticles reinforced diesel fuel along with various biogas (BG) flow rates (0.5, 1, and 2 L/min) on the engine performance and emission characteristics of a diesel engine. The tests were carried out using a single-cylinder, four-stroke, direct injection, compression-ignition engine at a constant engine speed of 1500 rpm and under the varying engine loads from 2.5 to 10 Nm with gaps of 2.5 Nm. In the results, it is seen that EGT started to decrease in both the addition of boron nanoparticles and the addition of biogas compared to that of conventional diesel fuel (DF). EGT reduced by 8.6% for DF+Boron test fuel, 14.4% for DF+Boron+ 0.5 BG, 21% for DF+Boron+ 1 BG, and 23.4% for DF+Boron+ 2 BG. Compared to diesel fuel, CO, NOx, and HC emissions decreased with the addition of nanoparticles at all loads. However, as the amount of biogas increased, CO and HC emissions increased, but NOx emissions decreased. CO emission dropped by 22.2% for DF+Boron test fuel, however, increased to be 5.6%, 16.7%, and 36.1% for DF+Boron+ 0.5 BG, DF+Boron+ 1 BG, and DF+Boron+ 2 BG respectively. NOx emission reduced by 4.9%, 8.6%, 10.7%, and 14.8% for DF+Boron, DF+Boron+ 0.5 BG, DF+Boron+ 1 BG, and DF +Boron+ 2 BG respectively. In comparison to that of conventional DF, the brake specific fuel consumption (BSFC) value decreased by 8.42% for DF+Boron test fuel due to high energy content of nanoparticles, but it increased by 10.94% for DF+Boron+ 0.5 BG, 28.01% for DF+Boron+ 1 BG, and 60.2% for DF+Boron+ 2 BG. In addition, brake thermal efficiency BTE value increased by 8.04% for boron-added test fuel, but it declined by 9.41% for DF+Boron+ 0.5 BG, 19.38% for DF+Boron+ 1 BG, and 32.2% for DF+Boron+ 2 BG as compared to that of DF. In the conclusion, it is noticed that the engine characteristics have worsened by the introduction of biogas into the cylinder, but these worsened characteristics can be improved with the presence of boron nitride nanoparticles. (c) 2022 Institution of Chemical Engineers. Published by Elsevier Ltd. All rights reserved.Öğe An experimental assessment on dual fuel engine behavior powered by waste tire-derived pyrolysis oil - biogas blends(Elsevier, 2022) Karagöz, Mustafa; Polat, Fikret; Sarıdemir, Suat; Yeşilyurt, Murat Kadir; Ağbulut, ÜmitThis paper is intended to investigate the usability of waste tire pyrolysis oil along with diesel and biogas dual fuel in the CI engines. In this framework, the waste tire chips are firstly pyrolyzed in the study, and then are volumetrically blended into the conventional diesel fuel (DF) at the ratio of 20%. The biogas flow rate changes as 0.5, 1, and 2 L/min when the engine is fuelled by P20 test fuel. Throughout the experiments, the engine runs at a fixed engine speed of 1500 rpm under 2.5, 5, 7.5 and 10 Nm. In the results, it is noticed that the unburnt emissions such as CO and HC considerably increases with the presence of pyrolysis oil and biogas in the cylinder due to the lack of oxygen and lower heating value of these fuels. However, the NOx firstly rises with the dieselpyrolysis oil blends by 2.21% but then pulls back with the introduction of biogas to the combustion chamber. It drops by 2.29%, 4.93%, and 11.14% for P20 + 0.5 BG, P20 + 1 BG, and P20 + 2 BG test fuels, respectively in comparison to that of DF. On the other hand, the engine performance worsens with the pyrolysis oil due to the lower energy content. Accordingly, the increment on BSFC is found to be 9.28%, 25.15%, 42.51%, and 67.68%, and the reduction on BTE is found to be 8.47%, 17.72%, 25.52%, and 33.48% for P20, P20 + 0.5 BG, P20 + 1 BG, and P20 + 2 BG test fuels, respectively. It is concluded that even if they worsen the engine performance and exhaust emissions, the burning of waste products in the forms of pyrolysis oil and biogas as fuel substitutions in CI engines seems a very promising way in terms of waste management, disposal the huge volume of waste products from the nature, and protection of rapidly depletion fossil fuel reserves.Öğe Experimental investigation of combustion, performance and emission characteristics of a diesel engine fuelled with diesel-biodiesel-alcohol blends(Springer Heidelberg, 2019) Ağbulut, Ümit; Sarıdemir, Suat; Albayrak, SerdarThe 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.Öğe Experimental investigation of performance, combustion and emission characteristics of a variable compression ratio engine using low-density plastic pyrolyzed oil and diesel fuel blends(Elsevier Sci Ltd, 2022) Rajak, Upendra; Panchal, Manoj; Veza, Ibham; Ağbulut, Ümit; Verma, Tikendra Nath; Sarıdemir, Suat; Shende, VikasPlastic waste adversely affects millions of people and wildlife habitat in many parts of the world. Although it could be utilized as a promising source of alternative fuel, its progress is not as advance as biodiesel or bioalcohol. Accordingly, a base fuel (BF) was blended with plastic pyrolyzed oil (PPO) to comprehensively investigate the usability of this product as a fuel substitute in compression ignition engines. Three fuels, BF100PPO0, BF80PPO20, and BF0PPO100, were tested and compared in a single-cylinder, 4-stroke, water-cooled VCR DI-CI engine that ran at five different compression ratios (15.5, 16.5, 17.5, 18.5, 19.5) under low, medium, and high engine loads. In the results, it is noticed that except for the maximum rate of pressure rise and ignition delay, raising the compression ratio from 15.5 to 19.5 did not result in significant changes. The results showed that BF80PPO20 produced the maximum BTE (34.4 percent) at CR 15.5 under high engine load, while BF100PPO0 produced the lowest BSFC (738.29 g/kWh) at CR 16.5 under high load. In terms of emissions, CO2 levels were found to be essentially same for all tested fuels at the greatest load for all compression ratios. Furthermore, with CR 19.5, BF80PPO20 was able to produce the lowest smoke emissions at medium load. In addition, at CR 15.5 and low engine load, BF100PPO0 produced the lowest NOx emissions (64.3 ppm). Overall, based on the findings of this research, plastic waste oil mixed with diesel fuel at a rate of up to 20% can be utilised as a promising biofuel to improve diesel engine performance, combustion, and emissions.Öğe Forecasting of future greenhouse gas emission trajectory for India using energy and economic indexes with various metaheuristic algorithms(Elsevier Sci Ltd, 2022) Bakır, Hüseyin; Ağbulut, Ümit; Gürel, Ali Etem; Yıldız, Gökhan; Güvenç, Uğur; Soudagar, Manzoore Elahi M.; Hoang, Anh TuanThe accelerating increment of greenhouse gas (GHG) concentration in the atmosphere already reached an alarming level, and nowadays its adverse impacts on the living organisms, environment, and ecological balance of nature have been well-understood. India is one of the top countries that contribute the most to global GHG emissions. Therefore, it is of great significance to forecast the future GHG trends of the country in advance and accordingly take measures against the parameters that cause these emissions, considerably. In this direction, the present research has centered on forecasting the greenhouse gas trajectory of India with various metaheuristic algorithms. In this framework, marine predators algorithm (MPA), lightning search algorithm (LSA), equilibrium optimizer (EO), symbiotic organisms search (SOS), and backtracking search algorithm (BSA) are used for modeling the future GHG emission trajectory of India. Accordingly, the significant economic and energy indicators of India such as renewable energy generation, electricity generation from coal, electricity generation from gas, electricity generation from oil, gross domestic product, and population between 1990 and 2018 are collected to make a nexus with GHG emissions. As GHG emissions, CO2, CH4, F-gases, N2O, as well as total GHG emissions are separately forecasted by the year 2050. To make a better comparison, each GHG emission data in the last year five years is used for the testing phase of the algorithms, and then statistically discussed in terms of R2, MBE, rRMSE, and MAPE benchmarks. In the results, it is found that the R2 value changes between 0.8822 and 0.9923 for CO2, 0.2855-0.9945 for CH4, 0.9-0.9904 for F-gases, 0.4655-0.9964 for N2O, and 0.9016-0.9943 for total GHG emission, and the results in terms of rRMSE are very satisfying for all algorithms. In the study, it is forecasted that the two greenhouse gas emissions with the highest increase rate in 2050 will be between 2.5 and 2.87 times for CO2 emissions and between 2.8 and 3.5 times for F-gases, compared to today's data. According to the results of the present paper, the total GHG emission for India is forecasted to be 2.1-2.4 times higher in the year 2050 as compared to today. Given all forecasting results together, it is seen that the MPA algorithm generally gives the best results according to the statistical metric results, while the LSA algorithm generally gives the worst results. Consequently, the present paper strongly reports that the decision-makers and policy-makersÖğe Forecasting of transportation-related energy demand and CO2 emissions in Turkey with different machine learning algorithms(Elsevier, 2022) Ağbulut, ÜmitAdverse impacts of the transportation sector on not only air quality but also economic growth of a country are nowadays well-noticed, particularly by developing countries. Today, the transportation sector is powered by burning the fossil-based fuels at more than 99% and approximately 6.5 million deaths annually occur due to air-pollution-related diseases worldwide. Therefore, knowledge of both energy demand and CO2 emission of a country is a very significant issue in order to revise its future energy investments and policies. In this framework, three machine learning algorithms (deep learning (DL), support vector machine (SVM), and artificial neural network (ANN)) are used to forecast the transportation-based-CO2 emission and energy demand in Turkey. The gross domestic product per capita (GDP), population, vehicle kilometer, and year are used as input parameters in the study. It is noticed that there is a very high correlation among year, economic indicators, population, vehicle kilometer, transportation-based energy demand, and CO2 emissions. To present a better comparison, the results of these algorithms are discussed with six frequently used statistical metrics (R-2, RMSE, MAPE, MBE, rRMSE, and MABE). For all machine learning algorithms, R-2 values are varying between 0.8639 and 0.9235, and RMSE is smaller than 5 x 10(6) tons for CO2 emission and 2 Mtoe for energy demand. According to the classifications in the literature, the forecast results are generally categorized as excellent for rRMSE metric (<10%), and high prediction accuracy for MAPE metric (<10%). On the other hand, with two mathematical models, future energy demand and CO2 emission arising from the transportation sector in Turkey are forecasted by the year 2050. In the results, it is fore-casted that the annual growth rate for transportation-related energy demand and CO2 emission in Turkey cumulatively rise by 3.7% and 3.65%, respectively. Both energy demand and CO2 emissions from the transportation sector in Turkey will increase nearly 3.4 times higher in the year 2050 than those of today. In conclusion, the paper clearly reports that the future energy investments of the country should be revised, and various policies, regulations, norms, restrictions, legislations, and challenges on both energy consumption and emission mitigation from the transportation sector should be established by the policy-makers. (C) 2021 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.Öğe Genleştirilmiş perlitin ısı yalıtım teknolojilerinde kullanılabilirliğinin incelenmesi(Pamukkale Univ, 2018) Uluer, Onuralp; Karaağaç, İbrahim; Aktaş, Mustafa; Durmuş, Gökhan; Ağbulut, Ümit; Khanlari, Ataollah; Çelik, Damla NurArtan nüfusla birlikte enerji ihtiyacındaki artış, enerji kaynaklarının etkili ve verimli değerlendirilmesini zorunlu hale getirmektedir. Uluslararası projeksiyonlara göre, bilinen rezervlerle dünyadaki en etkili enerji kaynaklarının yaklaşık 100 yıllık ömrü olduğu öngörülmektedir. Enerji kullanımının büyük bir kısmının binalarda olduğu gerçeği, birçok araştırma ile tespit edilmiş olup en büyük kayıp, ısı enerjisinde olmaktadır. Binalardaki ısı enerjinin korunması açısından ısı yalıtım malzemelerine olan ihtiyaç her geçen gün artmaktadır. Bu ihtiyaçları karşılamak için yeni teknoloji ve yeni malzeme arayışları sürmektedir. Bu çalışmada, dünya rezervlerinin %74’ü ülkemizde bulunan perlitin yapı sektöründe ısı yalıtımı amacıyla doğrudan ve/veya diğer yapı malzemelerinin ısıl özelliklerini iyileştirilmek amacıyla takviye malzemesi olarak kullanılabilirliği araştırılmıştır
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