Yazar "Polat, Fikret" seçeneğine göre listele
Listeleniyor 1 - 20 / 30
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe BLUETOOTH VE WİFİ KONTROLLÜ MOBİL ROBOT TASARIMI VE UYGULAMASI(Düzce Üniversitesi, 2018) Aktaş, Melih; Polat, Fikret; Oflezer, MuratEndüstri 4.0 ile hayatımıza girecek olan karanlıkfabrikaların sosyal hayatımızı etkilemesi kaçınılmaz bir gerçektir. Bu durumunsonucu olarak günlük hayatımızda robotların vazgeçilmez bir yerinin olacağı gözardı edilemez. Bu çalışmada konuyla ilgilenen herkesin kendisinin yapabileceğibir mobil robot uygulamasına yer verilerek robotların günlük hayatımızdakullanımının yaygınlaştırılması hedeflenmektedir. Kullanıcının isteğine görewi-fi veya bluetooth ile kolay kontrol edilebilme imkânı sunulmuştur. Mobilrobotumuzun gövdesi ise 3D yazıcı kullanılarak oluşturulmuştur.Mikrodenetleyici olarak NodeMCU kullanılmış ve eklenmiş olan mesafe sensörü ilearacın engellere çarpması önlenmiştir. Ayrıca eklenen sıcaklık, nem ve gazsensörleri ile ortam verilerine uzaktan erişim sağlanmıştır. Gaz sensöründenokunan değerlerin nominal değerleri geçmesi durumunda kullanıcıya bildirimgönderilmesi sağlanmıştır. Sensörlerdenokunan bu değerler wi-fi modül aracılığıyla uzaktan erişilebilir halegetirilmiştir. Bu çalışma konu ile ilgilenen araştırmacıların kendi mobilrobotlarını yapabilmelerine imkân sağlayan kapsamlı bir çalışma niteliğindedir.Öğe Catalytic combustion efficiency and emission reduction of amorphous boron/lanthanum orthoferrite nano-hybrids in hydrocarbon fuels(Pergamon-Elsevier Science Ltd, 2025) Kucukosman, Ridvan; Yontar, Ahmet Alper; Agbulut, Umit; Saridemir, Suat; Polat, Fikret; Unlu, Cumhur Gokhan; Ocakoglu, KasimThe effects of amorphous boron (AB) hybrid particles decorated with lanthanum orthoferrite particles on the combustion behavior and emission performance of conventional fuels were investigated. They are produced by combining ball-milling amorphous boron particles (AB/BM), Fe3O4 (F2) ferrite produced by sol-gel technique and La0.75Fe1.25O3 (LAF2) and LaFeO3 (LAF3) lanthanum ferrite nanoparticles by an ultrasonication technique. At 2.5 wt% (17353 ppm) particle load, the highest maximum flame temperature of gasoline-based nanofluid droplets was 644 K for AB-B.M., while at 7.5 wt% (52059 ppm) concentrations, the maximum aggregate temperatures were 642 K, 1358 K and 1298 K in the presence of nanohybrid structures based on AB-B.M., AB/LAF2 and AB/LAF3, respectively. At 2.5 wt% concentrations the lowest extinction time was recorded as 1321 ms for fuel droplets containing AB/LAF2 particles and at 7.5 wt% concentrations 1565 ms in the presence of AB-BM particles. According to the diesel engine test results, AB/LAF2 particulates have a 15 % and 17.6 % reduction in HRR compared to D100 at 15 Nm and 45 Nm respectively, and the largest reduction in BSFC values is 8.38 % and 7.99 % respectively at the same loads. At 60 Nm the highest decrease in CO emissions was 0.01 % in the presence of AB/LAF2 particles. The lowest HC emissions were observed in the presence of AB/LAF2 particulates, with 61.7 %, 42.85 %, 30.43 % and 41.37 % reduction in HC emissions compared to pure diesel at 15 Nm, 30 Nm, 45 Nm and 60 Nm respectively. At 30Nm, 45Nm and 60Nm, the lowest NOx emissions were recorded for the D100 + 250AB/LAF2 fuel, with reductions of 6.71 %, 9.33 % and 12.59 % respectively compared to D100.Öğe A comprehensive review of battery thermal management systems for electric vehicles(Sage Publications Ltd, 2022) Çetin, İrfan; Sezici, Ekrem; Karabulut, Mustafa; Avci, Emre; Polat, FikretTrying to prevent and mitigate carbon emissions and air pollution is one of the biggest challenges for the technological development of the automobile industry. In addition, the automobile industry has stepped up research and field applications of electric vehicles as the European Union encourages the restriction of the use of conventional fuel-powered vehicles such as diesel and gasoline vehicles. However, the cycle life, environmental adaptability, driving range, and charging time of the battery currently used in electric vehicles are far beyond comparison with internal combustion engines. Therefore, studies have focused on batteries, and battery thermal management systems (BTMSs) have been developed. Battery performance is highly dependent on temperature and the purpose of an effective BTMS is to ensure that the battery pack operates within an appropriate temperature range. Ensuring that the battery operates in the appropriate temperature range is vital for both efficiency and safety. To determine the best convenient BTMS for several types of battery packs attached to many factors such as volumetric constraints, installation costs, and working efficiency. The maximum temperature rise and the maximum temperature difference are the basic parameters to analyze the efficiency of the BTMS. Most of the research about thermal management has focused on especially air cooling, liquid cooling, and phase change material (PCM) cooling methods. In this study, different BTMSs (air cooling, liquid cooling, PCM cooling, etc.) were examined and their advantages and disadvantages were compared, usage restrictions in today's technology, requirements, and studies on this subject were reported.Öğe A comprehensive study on the influences of different types of nano-sized particles usage in diesel-bioethanol blends on combustion, performance, and environmental aspects(Pergamon-Elsevier Science Ltd, 2021) Agbulut, Umit; Polat, Fikret; Saridemir, SuatThis paper aims to discuss the influences of the doping of different types of nanoparticles into the bioethanol-diesel fuel blends on the combustion, performance, and emission aspects. In this viewpoint, the tests are performed at a constant engine speed of 2400 rpm under the varying engine loads from 3 to 12 Nm with the gaps of 3 Nm. Test engine is fuelled with conventional diesel fuel (DF), the binary form of 90% diesel fuel and %10 ethanol (DF90E10), and then separately 100 ppm aluminium oxide (Al2O3) nanoparticles (DF90E10 + A100), and 100 ppm titanium oxide (TiO2) nanoparticles (DF90E10 + T100) into DF90E10 test fuel. In the results, DF90E10 increases brake specific fuel consumption (BSFC) by 6.25% and drops the brake thermal efficiency (BTE) by 2.1% in comparison to those of conventional DF. However, it is noticed that nanoparticles-doped DF90E10 test fuels are being pulled back the worsened performance results thanks to their higher surface to volume ratio, higher cetane number, higher calorific value, superior thermal properties, catalyst role of the accelerating chemical reactions in combustion proces, and high energy density of nanoparticles. Accordingly, BSFC is dropped by 2.25% and 1.26% whilst BTE is enhanced by 3.48% and 2.94% for DF90E10 + A100 and DF90E10 + T100 test fuels, respectively as compared to those of DF. Thanks to the excess oxygen content of ethanol and oxygen-donating catalyst role of nanoparticles, carbon monoxide (CO) is reduced by 14.29%, 25%, and 21.43%, and hydrocarbon (HC) is reduced by 21.32%, 30.15%, and 26.47% for DF90E10, DF90E10 + A100, and DF90E10 + T100, respectively as compared to those of conventional DF. NOx emission increases by 3.6% for DF90E10, and then nitrogen oxides (NOx) are reduced by 3.02%, and 1.57% for DF90E10 + A100 and DF90E10 + T100 due to the higher thermal conductivity value of nanoparticles and improving engine performance characteristics. On the other hand, the highest in-cylinder pressure (CPmax) and heat release rate (HRRmax) values, and longer ignition delay are generally noticed for the diesel-ethanol binary blend due to the lower cetane number, lower energy density and higher viscosity. In conclusion, this paper is proving that the doping of nanoparticles into the biofuels is presenting very satisfying results in pulling back the worsened engine characteristics arising from using diesel-biofuel binary blends. (C) 2021 Elsevier Ltd. All rights reserved.Öğe 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 The effect of outer container geometry on the thermal management of lithium-ion batteries with a combination of phase change material and metal foam(Elsevier, 2024) Kursun, Burak; Toklu, Ethem; Polat, Fikret; Balta, MehmetThe use of PCM for thermal management of the batteries has an important place among passive cooling methods because it does not require pump or fan power. In battery cooling applications with PCM, it was aimed to increase the thermal conductivity of the PCM and to cool the battery better by using fins, nanoparticles, and metal foam. The novelty of this study is to investigate the effect of outer container geometry on battery temperature in battery cooling with PCM + metal foam composition. In this direction, five different container geometries affecting the heat transfer by conduction and convection were analyzed. The parametric study was carried out for different values of convection heat transfer coefficient, heat generation in the battery, PCM amount, and porosity. The lowest battery temperature for a given discharge time was obtained in triangular container geometry. With the use of a triangular container, the battery temperature was reduced between 0.4 % and 14.42 % compared to the use of a circular container, depending on the parameter values. The analysis findings revealed that the outer container geometry is more effective in the thermal management of the battery for conditions with low convection heat transfer coefficient and high heat generation.Öğe Effects of high-dosage copper oxide nanoparticles addition in diesel fuel on engine characteristics(Pergamon-Elsevier Science Ltd, 2021) Agbulut, Umit; Saridemir, Suat; Rajak, Upendra; Polat, Fikret; Afzal, Asif; Verma, Tikendra NathThis paper examines the effect of adding high dosage of copper oxide (CuO) nanomaterials (<77 nm) directly to conventional diesel fuel. The performance of the fuel with CuO added is assessed using a single cylinder, naturally aspirated, direct injection, air-cooled diesel engine. Examined were the char-acteristics of combustion and emissions for blends of 1000 and 2000 ppm CuO nanoparticles. The CuO blends were tested in the speed range between 2000 and 3000 rpm at intervals of 250 rpm. The CuO nanoparticles have the potential to accelerate the process of combustion by supplying molecules of oxygen and acting as a catalyst. The CuO enhances the thermal conductivity of the test fuels and in-creases heat dissipation from the combustion chamber. Experimental results show exhaust gas tem-perature (EGT) is reduced as well as unburnt hydro-carbons (HC) and oxides of carbon and nitrogen (CO and NOx). For CuO additions of 1000 and 2000 ppm, CO emissions fell by 14.6% and 20.8%, HC emissions by 6.2% and 13.4%, and NOx emissions by 4%, and 4.7%. Both blends of CuO increased the heating value of the diesel fuel. Brake-specific fuel consumption (BSFC) dropped by 4.5% and 8% while brake thermal efficiency (BTE) increased by 5.5% and 14.6% for 1000-CuO and 2000-CuO, respectively. On the other hand, nanoparticles accelerated the chemical reactions and the ignition delay (ID) period was shortened by 3.03% and 5.45% for CuO additions of 1000, and 2000 ppm, respectively. It was also observed that CuO nanoparticles up to 2000 ppm can be suspended in diesel fuel without clogging the filter on the injection system. (c) 2021 Elsevier Ltd. All rights reserved.Öğe ELEKTRİKLİ ARAÇLARDA KULLANILACAK BATARYA YÖNETİM SİSTEMİ GELİŞTİRİLMESİ(Düzce Üniversitesi, 2018) Maral, Yunus; Polat, Fikret; Aktaş, MelihDoğru akım (DC) ile çalışan, değişik güçlerdeüretilebilen, akımın verilen yönüne göre bir tarafı aşırı soğuyan diğer tarafıise aşırı ısınan elektronik aletlere peltier denir. Peltier, elektriksel olarakseri bağlı, ısı olarak paralel bağlı P ve N tipi yarı iletken malzemelerdenoluşur. Alt ve üst yüzeyi seramik kaplıdır. Seramik, ısıl olarak iletken,elektriksel olarak yalıtkan özelliği sağlar. Genel olarak peltierlerin COPdeğerleri düşüktür. Yani uzaklaştırmak istediğiniz yük için konvansiyonelbuzdolabı çevrimlerine (refrigeration cycle) oranla sisteme çok daha yüksek birenerji vermeniz gerekmektedir. Avantajları ise konvansiyonel buzdolabıçevrimlerine göre daha basit ve daha sorunsuz sistemlerdir. Bir dekonvansiyonel buzdolabı çevrimlerinde kullanılacak olan kompresörde belligüçlerin altına inildiğinde fiyatları artmakta ve verimlilikleri azalmaktadır(bu verimlilik azalması sonucu da sistemin COP’ si azalmaktadır). Bu çalışmadapeltier malzemelerin elektrikli araç bataryalarının soğutulmasında kullanılabilmekapasitesi araştırılmış ve batarya ünitesinin ısıl gücünün ölçümüyle ilgilideney düzeneği kurulmuştur. Deney düzeneğinde, sıcaklık değerlerini kayıt etmekiçin gerekli veri toplama sistemi, suyun debisini ölçmek için rotametre,sıcaklık ölçümleri için termokuple elemanları, veri toplama sistemini bağlamakiçin netbook bilgisayar, suyun giriş ve çıkış sıcaklıklarını okumak içingerekli karıştırıcı ara elemanlar (T-junction), pompanın devrinin kontrolünüsağlayan frekans kontrol cihazı bulunmaktadır. Yapılan deneyler sonucundaortam, su giriş-çıkış ve batarya sıcaklık değerleri ölçülmüş ve karşılaştırmalıolarak grafikler elde edilmiştir. Deneyler esnasında peltier ile bataryalarınetkin bir şekilde soğutulabildiği ve bataryanın güvenli sıcaklık aralığı olan-20 ile 60 derece arasında tutulabildiği gözlemlenmiştir.Öğe Energy, exergy, and emission (3E) analysis of hydrogen-enriched waste biodiesel-diesel fuel blends on an indirect injection dual-fuel CI engine(Pergamon-Elsevier Science Ltd, 2025) Bayramoglu, Kubilay; Bayramoglu, Tolga; Polat, Fikret; Saridemir, Suat; Alcelik, Necdet; Agbulut, UmitLimited fossil energy reserves and rising energy costs increase the importance of alternative renewable energy sources and more efficient use of energy. Hydrogen gas is an alternative renewable energy source for internal combustion engines due to its high combustion efficiency and lower calorific value and near-zero emissions. For more efficient and effective use of internal combustion engines, exergy analysis is also important along with energy analysis. In this study, biodiesel fuel obtained from waste cooking oil was blended with 20 % diesel fuel. Energy and exergy analyses were performed for the test fuels obtained by adding hydrogen at different ratios to the resulting fuel mixture. The experiments were carried out on a 3-cylinder, water-cooled, pre-combustion chamber diesel engine at a constant engine speed of 2200 rpm and under different loads (15 Nm, 30 Nm, 45 Nm and 60 Nm). Fuel energy ratio was calculated as 17.84 kW, 19.71 kW, 18.03 kW, 17.89 kW and 17.86 kW for D100, B20, B20H10, B20H20, B20H30 and B20H40 fuel blends, respectively. It was observed that heat loss increased by 10 %, mechanical energy rate increased by 100 % and exhaust energy rate increased by 57 % when 30 Nm torque energy flow rates were compared with 15 Nm torque case. Compared to 15 Nm engine load, fuel, exhaust, mechanical work and heat loss energy flow increases by 200 %, 300 %, 300 % and 100 % for 60 Nm engine load. The exergy destruction rate declines with increased engine loads. The exergy destruction rate constitutes approximately 46.7 % of the total exergy rate for 60 Nm engine load. The highest first- and second- law efficiencies for all test fuel are detected when the engine runs at 45 Nm. At this engine load, the first law efficiency is calculated to be 29.53 %, 27.91 %, 28.94 %, 29.4 %, 29.72 %, and 30.47 %, and the second law efficiency is calculated to be 27.62 %, 26.08 %, 27.05 %, 27.50 %, 27.81 %, and 28.52 % for D100, B20, B20+H10, B20+H20, B20+H30, and B20+H40.Öğe Energy, exergy, thermoeconomic, exergoeconomic, and sustainability analyses of hydrogen-enriched diesel-biodiesel nano fuels(Pergamon-Elsevier Science Ltd, 2025) Bayramoglu, Kubilay; Polat, Fikret; Bayramoglu, Tolga; Saridemir, Suat; Agbulut, UmitThis work intends to discuss the thermodynamic, economic, and sustainability analysis of hydrogen-enriched biodiesel-diesel and nanoparticle blends. In this direction, sunflower methyl ester (20 %) and diesel fuel (D100) are volumetrically blended (B20). Then, cerium oxide (CeO2) nanoparticles are added to B20 at a mass fraction of 100 ppm (B20CeO2). Furthermore, hydrogen of 5 lpm (B20CeO2H5) and 10 lpm (B20CeO2H10) is introduced into the combustion chamber from the intake manifold by mixing with the fresh air. The test engine is loaded from 15 to 60 Nm with increments of 15 Nm while it runs at a constant engine speed of 2000 rpm. The results show that the highest energy efficiencies are 28.9 % for B20CeO2H10 at 45 Nm. Besides, the highest exergy efficiencies are 27.01 % and B20CeO2H10 at 45 Nm. On the other hand, the best results are generally obtained for the B20CeO2H10 test fuel in terms of exergoeconomic and sustainability results. Crankshaft work has a particular work specific exergy cost of 138.9 US$/GJ for D100 and 184.6 $/GJ for B20CeO2H10. The sustainability index is determined as 1.37 for B20CeO2H10. In conclusion, these results reveal that adding nanoparticles and hydrogen considerably enhances the thermodynamic, economic, and sustainability metrics of the engine fuelled with diesel-biodiesel fuels.Öğe Enhancing diesel engine performance, combustion, and emissions reductions under the effect of cerium oxide nanoparticles with hydrogen addition to biodiesel fuel(Pergamon-Elsevier Science Ltd, 2024) Polat, Fikret; Saridemir, Suat; Gad, M. S.; El-Shafay, A. S.; Agbulut, UmitIn order to enhance engine combustion and emissions, inclusion of nano additives containing hydrogen is recommended due to the high viscosity, poor calorific value, atomization, and vaporization issues of biodiesel. Transesterification was used to transform sunflower oil into methyl ester. Sunflower biodiesel of 20% by volume was blended with diesel fuel, and CeO2 nanoparticles of 100 ppm were added to blends. Hydrogen was introduced by 5 and 10 lpm from intake manifold. Diesel engine operated at 2000 rpm and loads of 15, 30, 45, and 60 N m. BSFC was decreased by 1.77%, 4.71%, and 7.19% but BTE was improved by 1.39%, 4.04%, and 7.01% when cerium oxide, 5, and 10 lpm hydrogen were added to B20, respectively. When methyl ester mixture was combined with nano additive and H2 at 5 and 10 lpm, respectively, EGT was reduced by 2.62, 4.77, and 6.73%. B20+ CeO2 and B20+ CeO2+ 5 lpm, and B20+ CeO2+ 10 lpm showed decreases of 46.51%, 56.59%, and 63.57% in CO emissions but the declines in NOx were 6.34, 13.6% and 20.71%, respectively compared to diesel oil. Inclusion of nano-doped hydrogen at 5 and 10 lpm reduced HC emissions by 12.09% and 28.57%, respectively, about diesel. Hydrogen addition of 5 and 10 lpm to CeO2-doped B20 improved the in-cylinder pressures by 3% and 3.52% but the maximum heat release rate increases were 3% and 3.52% respectively compared to diesel. Biodiesel from sunflower oil with 100 ppm CeO2 with hydrogen shows reductions in emissions and combustion enhancement.Öğe Exergetic and exergoeconomic assessments of a diesel engine operating on dual-fuel mode with biogas and diesel fuel containing boron nitride nanoparticles(Springer, 2024) Uysal, Cuneyt; Agbulut, Umit; Topal, Halil Ibrahim; Karagoz, Mustafa; Polat, Fikret; Saridemir, SuatThis study investigates the exergetic and exergoeconomic analyses of a diesel engine operated on dual-fuel mode with fuelled both diesel fuel-boron nitride nanofuel and biogas purchased commercially. The experiments were performed for diesel fuel, diesel + 100 ppm boron nitride nanoparticle, diesel + 100 ppm boron nitride nanoparticle + 0.5 L min-1 biogas, diesel + 100 ppm boron nitride nanoparticle + 1.0 L min-1 biogas and diesel + 100 ppm boron nitride nanoparticle + 2.0 L min-1 biogas at various engine loads (2.5 Nm, 5.0 Nm, 7.5 Nm, and 10.0 Nm) and fixed crankshaft speed of 1500 rpm. The obtained experimental data were used to realize exergetic and exergoeconomic analyses. Among the fuels considered in this study, diesel + 100 ppm boron nitride nanoparticle nanofuel had the best exergetic and exergoeconomic results. As a result, at engine load of 10 Nm, the exergy efficiency of test engine and specific exergy cost of crankshaft work were obtained to be 29.12% and 124.86 US$ GJ-1 for diesel + 100 ppm boron nitride nanoparticle nanofuel, respectively. These values were 27.35% and 125.19 US$ GJ-1 for diesel fuel, 25.50% and 141.92 US$ GJ-1 for diesel + 100 ppm boron nitride nanoparticle + 0.5 L min-1 biogas, 23.10% and 156.33 US$ GJ-1 for diesel + 100 ppm boron nitride nanoparticle + 1.0 L min-1 biogas, and 21.09% and 171.92 US$ GJ-1 for diesel + 100 ppm boron nitride nanoparticle + 2.0 L min-1 biogas, respectively. It is clear that biogas addition to combustion made worse the exergetic and exergoeconomic performances of test engine. As a conclusion, it can be said that diesel + 100 ppm boron nitride nanoparticle nanofuel can be used as alternative fuel to D100 in terms of exergy and exergoeconomics.Öğe Experimental Analysis of The Impacts of Biodiesel-Diesel Fuel Mixtures on Engine Vibration, Noise and Combustion(Düzce Üniversitesi, 2023) Sarıdemir, Suat; Polat, FikretThe restricted reserves of fossil-based fuels and the regulations imposed on emission standards increase the importance of renewable fuels. Biodiesel is one of among peripherally friendly and renewable disjunctive fuels and contributes to the reduction of exhaust emissions. Biodiesel fuels have distinctive chemical frames and fuel features compared to conventional diesel fuels based on their substance and production method. Ignition delay, pressure increase rate, and combustion characteristics generate mechanical noises and vibrations in the engine. In compression-ignition engines, high noise and vibration eventuating from the explosive burning have negative effects on the environment and living beings. In this search, the impacts of various proportions of biodiesel fuel and conventional diesel fuel blends on the in-cylinder pressure, vibration, and noise of a three-cylinder water-cooled diesel engine were experimentally investigated. The peak max in-cylinder pressure values for all test fuels were obtained at 15 Nm. For all test fuels, the largest vibration value was obtained at 15 and 60 Nm and the smallest vibration value was obtained at 45 Nm. The engine noise level is reduced up to 45 Nm and increased at 60 Nm. The highest noise level was obtained with conventional diesel fuel (D) at all engine loads. The addition of biodiesel to the test fuels reduced the noise level at all loads. The average noise values of all test fuels are 90.58, 90.28, 90.35, and 90,09 dBA for 15, 30, 45, and 60 Nm loads, respectively.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 evaluation of the impacts of diesel-nanoparticles-waste tire pyrolysis oil ternary blends on the combustion, performance, and emission characteristics of a diesel engine(Elsevier, 2022) Polat, FikretIn the present research, pyrolytic oil is obtained from the waste tire chips, and then acid washing process, clay and calcium oxide process, distillation process, and oxidative sulfur removal processes are used to improve its properties. Then it is blended into conventional diesel fuel with/without Al2O3 nanoparticles, and the performance, combustion, and emission characteristics of a single-cylinder, air cooled, and naturally aspired diesel engine are discussed in this study. Tests were performed at varying engine loads from 3 to 12 Nm with the gaps of 3 Nm under a constant engine speed of 2400 rpm. In this study, three types of fuels were tested, namely D100 (100% diesel fuel), P10 (90% diesel fuel and 10% pyrolytic oil), and P10 + 1 g Al2O3 (obtained by adding 1 g of Al2O3 nanoparticles to P10 fuel). The addition of Al2O3 nanoparticles increased the brake thermal efficiency while reducing the maximum in-cylinder pressure, heat release rate, specific fuel consumption, exhaust gas temperature, hydrocarbon emissions, NOx emissions, and CO emissions compared to other test fuels. Namely, with the addition of Al2O3 nanoparticles, BTE was improved by 4.51% and 1.59% compared to P10 and pure diesel fuel, respectively. According to this, the BSFC value increased by 4.29% for P10 test fuel and then is reduced by 2% for P10 + 1 g Al2O3 test fuel as compared with conventional diesel fuel. Compared to diesel fuel, the CO, NOx, and HC emission values deteriorated by 17.5%, 5.69%, and 18.6%, respectively, with the addition of pyrolysis oil, and these deteriorated properties were improved by 10%, 6.82%, and 13.95%, respectively, with the addition of Al2O3 nanoparticles. In the light of this study, it was observed that while waste tire pyrolysis oil worsened engine performance, emission, and combustion characteristics, these deteriorations could be improved with nano Al2O3 supplementation. (c) 2022 Institution of Chemical Engineers. Published by Elsevier Ltd. All rights reserved.Öğe Faz Değişim Malzemesi Olarak Parafinin Bir Batarya Termal Yönetim Sisteminin Soğutma Performansı Üzerindeki Etkisinin Deneysel Olarak İncelenmesi(Düzce Üniversitesi, 2023) Polat, Fikret; Sarıdemir, Suatİçten yanmalı motorlar (İYM'ler) büyük ölçüde fosil yakıtlara bağımlıdır ve hem fosil yakıtların tükenme riski hem de içten yanmalı motorların yaydığı zararlı egzoz emisyonları araştırmacıları elektrikli araçlara (EA) ilgi duymaya yöneltmiştir. Elektrikli araç sektörünün her geçen gün gelişmesiyle birlikte, elektrikli araçların en önemli bileşeni olan pillerin yüksek sıcaklık sorununun çözümünde batarya termal yönetim sistemleri (BTYS) vazgeçilmez hale gelmiştir. Elektrikli araçların maliyeti ve güvenilirliği, kullanılan pil paketinin ömrü, kapasitesi, şarj süresi, dayanıklılığı ve garanti maliyeti gibi parametrelerden etkilenmektedir. Batarya paketinde üretilen ısı, aktif soğutmada gaz veya sıvı soğutmayla, pasif soğutmada ise faz değiştiren malzemeler (FDM) ile uzaklaştırılır. FDM'lerin enerji depolama yoğunluğunun yüksek olması ve FDM'ler kullanılarak yapılan soğutmada fan veya pompa gücüne ihtiyaç duyulmaması, FDM'lerin batarya termal yönetim sistemlerinde tercih edilmesinin nedenlerinden bazılarıdır. Bu çalışmada, 6'sı seri, 3'ü paralel olmak üzere 18 adet lityum iyon pilden oluşan bir pil paketi, önce herhangi bir soğutma sistemi olmadan, ardından 1C akım gücünde FDM ilavesi ile şarj ve deşarj edilmiş ve batarya termal yönetim sisteminin etkisi incelenmiştir. BTYS'nin batarya paketindeki maksimum sıcaklık değeri açısından şarj deneylerinde yaklaşık %8, deşarj deneylerinde ise %23 oranında pozitif etkiye sahip olduğu görülmüştür.Öğe Improvement of worsened diesel and waste biodiesel fuelled-engine characteristics with hydrogen enrichment: A deep discussion on combustion, performance, and emission analyses(Elsevier, 2024) Saridemir, Suat; Polat, Fikret; Agbulut, UmitDue to the strict emission policies, fuel researchers are dedicated to mitigating the tailpipe emissions from internal combustion engines (ICEs). Therefore, researchers have considered biodiesel as the best alternative to conventional diesel fuel (D) for a while. However, many scientific papers experimentally announced that the use of biodiesel significantly worsens engine behaviors. In this framework, hydrogen enrichment has become a very reasonable option in order to minimize the reverse influences of biodiesel-fuelled engine characteristics. In this direction, waste cooking of 25% (B25) was volumetrically blended to D and reference data was collected. Then, 15 and 30 Lpm hydrogen was introduced from the intake manifold by mixing with air along with B25 test fuel to observe the changes from the hydrogen effect. Tests were performed on a three-cylinder, water-cooled diesel engine at constant engine speed (2000 rpm) and variable engine loads (15, 30, 45 and 60 Nm). In the results, it is witnessed that BSFC (brake specific fuel consumption) for B25 fuel increased by 8.23% as compared D fuel. However, along with the introduction of 15 and 30 Lpm hydrogen to B25 fuel, the BSFC value dropped by 17.58%, and 30.75%, respectively. In a similar way, B25 test fuel reduces BTE (brake thermal efficiency) by 7.54% as compared to D fuel. However, the hydrogen introduction of 15 and 30 Lpm (Litre per minute) along with B25 fuel improves the BTE value by 10.19%, and 17%, respectively. On the other hand, the inclusion of 15 Lpm and 30 Lpm H2 to B25 fuel provided a reduction of 23.75% and 45.59% for HC (Hydrocarbon) emissions, and 53.1% and 62.6% for NOx (Nitrogen oxide) emissions, respectively. In conclusion, it is seen that deteriorations in combustion, performance, and emission characteristics resulting from the use of biodiesel can be minimized by using hydrogen for ICEs.Öğe Influence of A Novel Catalysis on The Pyrolysis Yields Obtained by Two Different Reactors(2020) Toklu, Ethem; Polat, Fikret; Kılınçel, MertIn the present study mixtures of polymeric and cellulosic biomass materials were pyrolized in the presence of two different catalysts (sepiolite and aluminium bauxite) in various ratios by two different reactors; a rotary kiln reactor (RKR) and a fixed bed pyrolysis reactor (FBR). The results were compared to determine the effects of pyrol ysis parameters such as catalysts, feedstock and reactor types on the energy content of the final products. First, the polymeric and cellulosic materials were mixed at certain ratios and thus the mixtures were prepared. Then, thermally activated catalysts were added to these mixtures. At the end of the experiments, certain properties such as higher heating value (HHV), the elemental concentrations, particle size and size surface areas of the end products (for solid and liquid phases) were calculated and analysed. The HHV of the liquid products from bauxite added mixture in RKR and FBR was 42.74 MJ/kg and 40.95 MJ/kg respectively. Besides the HHV of the oil products from sepiolite added mixture in RKR and FBR was 41.28 MJ/kg and 38.94 MJ/kg respectively. These values are same and close to HHV of the conventional diesel (42.7 MJ/kg). However no considerable effect seen on HHV of char products from catalyst added mixtures. On the other hand, due to the SEM images the char products it can be clearly concluded that com paring with FBR, RKR had the better performance on pyrolysis of the biomass mixtures.Öğe Investigation of the effects of different nanoparticle-reinforced liquids on the cooling performance of the battery thermal management system(Springer Heidelberg, 2024) Celik, Kemal; Polat, Fikret; Kilincel, MertElectric vehicles are gaining importance in the transportation sector as an environmentally friendly option to replace fossil fuels and reduce carbon footprint. Battery packs, which are the power source of electric vehicles, are high-cost and thermally sensitive components. The temperature rising and temperature distribution of battery packs during charging and discharging processes affect their performance, life, and safety. Therefore, an effective cooling system is required to keep the operating temperature of the battery packs in the optimum range and to ensure homogeneous temperature distribution. In this study, a battery module containing 18 cylindrical lithium-ion batteries was placed in a labyrinth-type cooling channel. The cooling channel is made of copper. Pure water, boron nitride (BN)-water nanofluid, and titanium dioxide (TiO2)-water nanofluid were passed through the cooling channel and the thermal performances of the cooling fluids were compared. Concentrations of 0.1% by mass of BN-water nanofluid and 0.1% by mass of TiO2-water nanofluid were used. Experiments were carried out at 1C charge and 1C, 2C, and 3C discharge rates to test the battery pack under different operating conditions. In all experiments, the inlet flow rate of the refrigerants was kept constant at 790 ml/min and the inlet temperature at 25 degrees C. According to the experimental results, it was seen that BN-water nanofluid provides better cooling performance compared to other fluids and makes the temperature distribution of the battery module more homogeneous. This study aims to contribute to the development of battery thermal management systems in electric vehicles.
