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Öğe Assessment of trade-off, exergetic performance, and greenhouse gas impact-cost analysis of a diesel engine running with different proportions of TiO2, Ag2O, and CeO2 nanoadditives(Pergamon-Elsevier Science Ltd, 2024) Gülcan, Halil Erdi; Erol, Derviş; Çelik, Mehmet; Bayındırlı, CihanIn this study, the effects of adding different proportions of TiO2, Ag2O, and CeO2 nanoparticles to a threecylinder, water-cooled, four-stroke, direct injection diesel engine on engine performance and exhaust emissions are experimentally investigated. The experiments are conducted at four different engine loads (10, 20, 30, and 40 Nm) and a constant engine speed (1800 rpm). TiO2, Ag2O, and CeO2 nanoparticles are added to the diesel fuel at concentrations of 50 and 75 ppm each. The test fuels used in the study are as follows: D100, DTi50, DTi75, DAg50, DAg75, DCe50 and DCe75. Using the experimental results, analyses of energy, exergy, sustainability, greenhouse gas (GHG) emission impact, and cost are performed. The experimental results reveal that the use of nanoparticles in diesel fuel reduces BSFC. The highest reduction in BSFC is achieved with DTi75 fuel, averaging 9 %. Additionally, DTi75 fuel shows an average increase of 19 % in NOx emissions compared to D100 fuel, while smoke emissions decrease by an average of 30 %. The highest average increase in exergy efficiency compared to D100 fuel is obtained with DAg50 fuel (5.6 %), followed by DTi75 fuel (5.3 %). The addition of nanoparticles to diesel fuel also leads to an increase in GHG emissions. Compared to D100 fuel, the highest average contribution to GHG emissions increase is shown by DTi75 fuel (12 %), while the lowest average contribution is observed with DAg50 fuel (4 %).Öğe Application of Higher-Order Alcohols (1-Hexanol-C6 and 1-Heptanol-C7) in a Spark-Ignition Engine: Analysis and Assessment(Springer Heidelberg, 2021) Yaman, Hayri; Doğan, Battal; Yeşilyurt, Murat Kadir; Erol, DervişStudies on the usage of gasoline-alcohol blends as an alternative fuel in spark-ignition engines have recently gained momentum. In the present research, energy, exergy, environmental, enviroeconomic, exergoenvironmental, and exergoenviroeconomic analyses were conducted with the performance and emission values acquired by utilizing gasoline, gasoline-heptanol, and gasoline-hexanol fuels (G100, HEX5-20, and HP5-20) as a fuel under different powers at a constant speed of 1600 rpm in a single-cylinder four-stroke spark-ignition engine. As the ratio of alcohol in fuel blends increases, fuel consumption also increases. NOX emission is higher, and CO and HC emissions are lower in alcohol-based fuel blends than G100 fuel. The highest thermal efficiency is 41.09% in G100 fuel at a power of 5 kW. As the ratio of alcohol in fuel blends increases, thermal efficiency decreases. The highest exergy destruction and entropy generation were determined to be 6.25 kW and 0.02134 kW/K, respectively, in HP20 fuel at a power of 5 kW. Entropy generation increases with an increase in the ratio of alcohol in alcohol-based fuels. HEX20 and HP20 fuels produce 25% and 30% more entropy, respectively, compared to G100 fuel. The mass and financial costs of the damage caused by the CO2 emission of fuels to the environment were determined by conducting four different analyses using energy and exergy analysis data. According to the exergoenvironmental and exergoenviroeconomic analyses, HP20 fuel reached the highest environmental pollution values of 4538.19 kg CO2/month and 65.804 $/month, respectively. The environmental cost of the CO2 emission released from the exhaust to the atmosphere is higher in alcohol-based fuels than G100 fuel. As a result of all analyses, it was concluded that hexanol and heptanol could be alternative fuels in spark-ignition engines under particular conditions.Öğe An experimental comparative study of the effects on the engine performance of using three different motion mechanisms in a beta-configuration Stirling engine(Pergamon-Elsevier Science Ltd, 2024) Erol, DervişThis study deals with three different Stirling engines with rhombic, slider-crank, and bell-crank motion mechanisms which have been designed and manufactured. Engine performance tests of Stirling engines with these three different motion mechanisms at different operating parameters have been carried out in a laboratory environment. During the experimental studies under consideration, the cooler and heater temperatures have been kept at 300 K (+/- 5) and 1000 K (+/- 10), respectively. Engine performance tests have been performed at different charging pressures using helium, nitrogen, and air as working fluids. Despite the fact that the Stirling engines with these three different motion mechanisms have the same sweeping volumes and technical specifications, engine performance values have been obtained differently from each other. The main reason for this difference can be explained as friction and other mechanical losses in motion mechanisms. The performance values obtained depending on the type of motion mechanism are rhombic, slider-crank, and bell-crank, from highest to lowest, respectively. The highest engine power measured among all experimental studies has been 215.48 W at 550 rpm and 4 bar charging pressure in tests using helium gas and rhombic motion mechanism. The lowest engine power among the maximum power values has been obtained as 82.5 W at 167 rpm and 4 bar charging pressure in experiments using air as the working fluid and the bell-crank motion mechanism. As a matter of fact, the highest engine power within the maximum engine power values is 161.2% higher than the lowest engine power.Öğe Activity of nanosized copper-boron alloys against Phytophthora species(Springer, 2024) Yiğit, Uğur; Türkkan, Muharrem; Ilhan, Hasan; Şimşek, Tuncay; Güler, Ömer; Derviş, SibelThis study aimed to evaluate the antifungal activity of copper-boron (Cu-B) nanoalloys against a range of Phytophthora species, including P. capsici, P. citrophthora, P. palmivora, P. cinnamomi, P. nicotianae, P. cactorum, P. plurivora, P. inundata, and P. megasperma. The nanoalloys were synthesized via mechanical alloying under an argon atmosphere, resulting in the formation of nanocrystalline Cu-B nanoalloys with irregular morphology and particle sizes ranging from 50 to 240 nm. At a concentration of 250 mu g mL(-1), the Cu-B nanoalloys demonstrated complete inhibition of mycelial growth, sporangium production, and zoospore germination in all tested Phytophthora species. The EC50 values for mycelial growth ranged from 28.02 to 120.17 mu g mL(-1), while for sporangium production and zoospore germination, they were below 10 mu g mL(-1). Furthermore, the nanoalloys exhibited fungicidal activity against specific Phytophthora species, such as P. capsici, P. citrophthora, P. inundata, and P. megasperma, at concentrations of 100, 250, 250, and 250 mu g mL(-1), respectively. Notably, the Cu-B nanoalloys displayed significant protective and curative effects on tuber rot severity in P. nicotianae-inoculated potatoes, resulting in reductions of 94.13% and 92.61% compared to the control, respectively, at a concentration of 10 mu g mL(-1) (P < 0.05). These findings highlight the potential of Cu-B nanoalloys as a promising fungicide for the management of plant diseases caused by Phytophthora spp.Öğe A review of soft magnetic properties of mechanically alloyed amorphous and nanocrystalline powders(Springernature, 2023) Yakın, Alican; Şimşek, Tuncay; Avar, Barış; Şimşek, Telem; Chattopadhyay, Arun K.The development of soft magnetic materials is fundamentally important for improving operational efficiencies of the ever-growing field of power electronics, electrical motors, and generators. It requires to meet the challenges of constantly changing fields of modern areas of applications starting from spaceships to day-to-day electronics. Many new materials with soft magnetic properties, viz. ferrous alloys, soft ferrites, amorphous and nanocrystalline magnetic alloys, have been continuously evolving since the inception of electromagnetic induction. The main drive for the continuous improvements of soft magnetic materials is primarily to enhance energy efficiency, to reduce size and weight, and to boost the power of high-frequency power electronics and electrical machines of high rotational speed. Despite some predicaments, the amorphous and nanocrystalline soft magnetic materials have become a field of major research interest since their invention four decades ago. It has been observed that the amorphous and nanocrystalline alloys exhibit better magnetic properties than the conventional soft magnetic alloys. This group of materials is produced adapting various production techniques. In this review, amorphous, nanocrystalline, and high entropy alloys (HEA) are discussed as soft magnetic materials and their electromagnetic properties are assessed. However, this review will particularly focus on the mechanically alloyed amorphous, nanocrystalline, and HEA soft magnetic materials. The soft magnetic alloys of interest for this review are grouped on the basis of Fe, Co, Ni, and FeCoNi. Furthermore, the effect of MA parameters and subsequent annealing processes on the magnetic properties is also assessed. This review brings forth a great promise in the field of soft-core magnets for high-end applications.Öğe A detailed analysis of a diesel engine fueled with diesel fuel-linseed oil biodiesel-ethanol blends in a thermodynamic, economic, and environmental context(Ecopetrol Sa, 2023) Ibrahim, Gehad Yasser Aly Maher; Atak, Nisa Nur; Doğan, Battal; Yeşilyurt, Murat Kadir; Yaman, HayriThe growing demand for energy, coupled with volatile oil prices and the environmental damage caused by the harmful gases produced when it is used, has prompted countries to explore alternative energy sources. The transportation sector, an important end-user of petroleum, must adapt to the changing energy landscape and opt for new technologies to remain competitive. The study conducted a thorough thermodynamic analysis to assess the economic and environmental impact of using biodiesel (BD) made from cold-pressed linseed crude oil, commercial diesel fuel (DF), and ethanol in a compression-ignition (CI) engine. The study conducted a detailed thermodynamic analysis of performance and emission data recorded from a single-cylinder diesel engine. The analysis included energy, exergy, sustainability, exergoeconomic, exergoenvironmental, and exergoenviroeconomic parameters. The results pointed out that the fuel energy increases with the load, with B20E5 fuel reaching 6.887 kW at 25% load and 18.908 kW at 75% load. BD and blended fuels were found to have a higher fuel energy compared to DF. At 50% load, DF and B20 fuels have fuel energies of 10.765 kW and 10.888 kW, respectively. The analysis clearly demonstrates that commercial DF outperforms both DF-BD binary fuel blends and DF-BD-ethanol blends in terms of thermal and exergy efficiency values. Furthermore, DF exhibits lower entropy generation and exergy destruction than other binary and ternary blends. At maximum load, the exergy efficiencies of DF, B20, and B20E10 fuels were 28.5%, 25.8%, and 24.7%, respectively. The exergy losses were determined to be 10.495 kW, 12.317 kW, and 13.134 kW, respectively, under the same conditions. Binary and ternary fuel blends have a higher cost of power from the engine shaft due to the expensive market prices of ethanol and linseed oil-based BD compared to DF. However, B20 and B20E10 fuels have a lower environmental cost than DF, with B20 and B20E10 fuels estimated to be 2.8% and 5.3% lower than DF, respectively, at full load. These findings demonstrate the clear advantages of using B20 and B20E10 fuels over DF, both in terms of cost and environmental impact. Additionally, the infusion of ethanol into ternary blends reduces the environmental damage. This study provides a unique perspective on sustainable energy research and serves as a valuable reference for future studies.Öğe Experimental assessment of a CI engine operating with 1-pentanol/diesel fuel blends(2020) Yeşilyurt, Murat; Doğan, Battal; Erol, DervişAlcohols have been known as influential alternatives for the utilization in the compression-ignition (CI) engines. In contrast to lower-order alcohols such as methanol-C1 and ethanol-C2, long-chain alcohols (higher-order alcohols) have a hopeful future for CI engines. Pentanol-C5 or amyl alcohol, regarding its affirmative chemical and physical properties, is a type of higher alcohol that can be obtained from biomass resources and hence it has to be evaluated as an alternating and sustainable fuel candidate in diesel engine applications. The objective of this work is to explore the engine performance and exhaust emission characteristics of a CI engine running on 1-pentanol/diesel fuel mixtures. For this aim of the experimental research, three different blends were created by infusing various ratios (10, 20, and 30% by volume) of 1-pentanol into pure diesel with implementing the splash-blending method to acquire the binary blends of Pt10, Pt20, and Pt30. The tested fuel samples were used in a single-cylinder diesel engine coupled with a generator. The influences of a next-generation alcohol addition to the diesel upon the engine performance along with exhaust emission levels of the tested engine were meticulously researched at six different engine loads (0, 0.4, 0.8, 1.2, 1.6, and 2 kW) with a stable speed (3000 rpm). The infusion of alcohol into the diesel fuel declined cetane number as well as the lower calorific value of the fuel blends. As a result of the study carried out, it was observed that the brake specific fuel consumption (BSFC) increased between 4.46- 11.78% averagely as the ratio of 1-pentanol in the mixtures increased while brake thermal efficiency (BTE) and exhaust gas temperature (EGT) dropped up to 6.75% and 6.69%, respectively owing to the lesser energy content of the 1- pentanol. When the test engine operating with binary blends, unburned hydrocarbon (HC) and carbon monoxide (CO) emissions were obtained to be higher than that of conventional diesel fuel due to the higher latent heat of vaporization (LHV) of 1-pentanol resulting in a cooling impact in the cylinder, leading descending trend in the efficiency of the combustion. Besides, the addition of 1- pentanol to diesel caused the mitigation in smoke emission by 77.37-89.60%, carbon dioxide (CO2) by 13.06-30.83%, and nitrogen oxides (NOX) by 13.43- 41.61% on an average as compared to diesel fuel. Overall, it has been shown up that 1-pentanol might be successfully utilized as an oxygenated fuel additive to diesel fuel, however in a minimum concentration of 1-pentanol, i.e., Pt10 blend has provided luminous outcomes in terms of mitigating the EGT, smoke opacity, and especiallyNOXemissions, however at the expense of boosting in the emissions of CO and HC.Öğe The investigation of exergoeconomic, sustainability and environmental analyses in an SI engine fuelled with different ethanol-gasoline blends(INDERSCIENCE ENTERPRISES LTD, 2020) Doğan, Battal; Erol, Derviş; Kodanlı, EvrenIn this study, performance and emission values were obtained under full load by using ethanol-gasoline blends as a fuel at different rates in a spark-ignition engine, and exergy, exergoeconomic and environmental analyses were performed with these values. Exergy of a fuel entering engine and lost exergies through cooling system, exhaust and radiation were calculated. CO, CO2, HC, and NO(X)emissions released from engine into environment were measured, and according to environmental analysis, cost of CO(2)emission was calculated as 393.78 USD/year for E0 fuel and as 306.78 USD/year for E30 fuel at 2,000 rpm. Ethanol-gasoline blends at different rates, environmental damage can be reduced by around 30% on an annual basis. Furthermore, with environmental analysis, lowest engine output power cost was found to be 29.77 USD/MJ in E0 fuel at 2,000 rpm, while highest engine output power cost was found to be 120 USD/MJ in E30 fuel at 4,500 rpm.Öğe Investigation on 1-heptanol as an oxygenated additive with diesel fuel for compression-ignition engine applications: An approach in terms of energy, exergy, exergoeconomic, enviroeconomic, and sustainability analyses(ELSEVIER SCI LTD, 2020) Dogan, Battal; Cakmak, Abdulvahap; Yesilyurt, Murat Kadir; Erol, DervisStudies on alternative and environmentally friendly fuels for compression-ignition engines continue intensively. In this work, energy, exergy, exergoeconomic, enviroeconomic, and sustainability analyses have been conducted by evaluating performance and emission values obtained by operating with different ratios of 1-heptanol/diesel blends (Hp0, Hp5, Hp10, and Hp20) as novel fuels under a constant speed (1500 rpm) with different engine loads (25%, 50%, 75%, and full load) in a single-cylinder, four-stroke, water-cooled, direct-injection, compression-ignition engine. In the test engine, energy and exergy efficiencies and losses, energetic and exergetic powers, irreversibility, and destruction of the exergy for the aforementioned fuel blends have been calculated and compared with pure diesel fuel. In the tests, the highest fuel consumption was determined as 0.221 kg/kWh in HP20 fuel at 100% load because 1-heptanol has lower calorific value than that of neat diesel fuel. The energy efficiency values in different loads of diesel engine for all fuel blends (Hp0-Hp20) have been calculated to be as between 14.46% and 40.72% along with the corresponding exergy efficiency values have been found to be as between 13.43% and 37.79%. By performing emission measurements, the highest CO2 emission cost has been calculated as 66.94 USD/year at a 100% load in Hp10 fuel according to the enviroeconomic analysis. In this present research, by implementing the exergoeconomic analysis, the highest engine output power cost at a load of 25% has been noted to be at 1.6 USD/MJ for Hp20 blend. Sustainability analysis has been determined according to the SI index, and the highest index was calculated to be 1.6 at a 100% load for Hp0 fuel.Öğe Preparation of single-phase YbB(6)by low-temperature solid-state reaction method using iodine(SPRINGER, 2020) Simsek, TuncayIn this study, low-temperature solid-state synthesis of pure nanocrystalline ytterbium hexaboride (YbB6) employing iodine-based reduction method has been discussed. For the reduction reaction, the mechanically activated powder mixture of ytterbium oxide, boron oxide, magnesium, and iodine was heated up under Ar in a quartz tube to 85 degrees C. All reaction byproducts, viz. MgO, Mg-3(BO3)(2), and YbI2, were removed by hot acid leaching with 3 M HCl solution to form pure YbB6. The morphological and phase structure of the synthesized YbB(6)powder were analyzed by X-ray diffractometry (XRD), high-resolution transmission electron microscopy (HRTEM), and Raman spectroscopy. The crystalline phases obtained were refined by multi-phase Rietveld refinement. XRD and Raman spectroscopy showed a contrast between the nano-YbB(6)formed by the present low-temperature iodine-based reduction method versus mechanochemical method. The YbB(6)produced by the low-temperature iodine reduction method is highly crystalline in nature, whereas YbB(6)produced by mechanochemical method is less crystalline or conversely more amorphous in nature. The iodine-based reduction method indeed played a definitive role to allow the reaction to take place at a lower temperature enabling the formation of nanocrystalline YbB6.Öğe Comparative study on the performance of different drive mechanisms used in a beta type Stirling engine through thermodynamic analysis(2019) Erol, Derviş; Çalışkan, SinanIn this study, thermodynamic and kinematic analyses of bell crank, slidercrank, rhombic and scotch yoke drive mechanisms were performed for a betatype Stirling engine with a swept volume of 365 cm3. The kinematic analysesof Stirling engines with these different drive mechanisms were investigated byusing the MSC Adams program, and the pressure-volume variations dependingon the crankshaft angle were determined by using the isothermal analysismethod. It was determined that compression and expansion volume values ofrhombic drive mechanism were close to each other, while compression volumevalue was extremely higher than expansion volume value in other drivemechanisms. For this reason, in this research conducted with working fluid ofequal amount (m0.000716 kg), for all of drive mechanisms, it was determinedthat engine with rhombic drive mechanism generates 19.2% net work morethan the other drive mechanism. The masses of working fluid used in 1 barcharge pressure from engines with bell crank, slider crank, rhombic and scotchyoke drive mechanism were 0.000716 kg, 0.000737 kg, 0.000536 kg and0.000724 kg, respectively. The net work amounts obtained as a result of thethermodynamic analyses made for the 1 bar charge pressure value in bell crank,slider crank, rhombic and scotch yoke drive mechanisms are 12.85 J, 12.44 J,11.61 J and 13.05 J, respectively. In this research conducted with working fluidin the same charge pressure, it was determined that 10.8% less net work wasobtained from engine with rhombic drive mechanism. Since all the changes ofthe volume in the bell crank, slider crank and scotch yoke drive mechanismsare very close to each other, the net work performance values obtained withthe equal amount of working fluid and the same charge pressure values are alsovery close to each other.Öğe Selection of Tool Path and Parameter in Computer Aided Production of Belt Pattern Mold(2015) Başkal, TamerBu çalışmada, deri kemer üzerinde bulunan 3 boyutlu sanatsal rölyef desenlerin oluşturulmasında kullanılan sıcak baskı kalıplarının üretiminde CNC takım yolu ve parametreleri araştırılmıştır. Kemer üzerinde baskı kalıplarıyla elde edilen 3 boyutlu rölyef desenler sıcak baskı ile kemer boyunca basılan izlerden oluşmaktadır. Bu çıkıntı ve girintiler, kemerde çeşitli sanatsal görüntüler oluşturarak giyim dünyasında çeşitliliği oluşturmaktadır. Kemer üzerindeki desenler, kemer boyutundaki pirinç lama malzemeler üzerine CAD-CAM programları sayesinde işlenen CNC tezgahı üretimler ile elde edilmektedir. Bu çalışmada, bir rölyef desen kalıbının üretiminde kullanılan CAM programıyla seçilen takım yolu ve parametre değerleri gösterilmiştir.
