Yazarlar
- Akkurt, Nevzat(24)
- Kahraman, Gökhan(17)
- Sabanci, Serdal(11)
- Tuğan, Volkan(9)
- Işık, Erdem(8)
- Xu, Qian(8)
- Xiong, Yaxuan(7)
- Yucesan, Melih(7)
- Goksu, Ali(6)
- Demir, Yakup(5)
- Gul, Muhammet(5)
- Aghakhani, S.(4)
- Cevik, Mutlu(4)
- Icier, Filiz(4)
- Liu, Lin(4)
- Mahmoud, Mustafa Z.(4)
- Taşgın, Yahya(4)
- Yang, Gang(4)
- Yardımcı, Uğurcan(4)
- Younis, Obai(4)
- Yüzüak, E.(4)
- Yüzüak, G. Durak(4)
- Yüzüak, Gizem Durak(4)
- Çevik, Mutlu(4)
- Özdemir, Osman(4)
- Chen, Xingli(3)
- Ding, Yulong(3)
- Du, Yanping(3)
- Erdem, Necla Seval(3)
- Gunay, Mihriban(3)
- Göçmen, Elifcan(3)
- Hussein, Ahmed Kadhim(3)
- Karakaya, Hakan(3)
- Konurhan, Zekeriya(3)
- Qiang, Yujie(3)
- Sabancı, Serdal(3)
- Wang, Zhaoxiao(3)
- Yilmaz, Mehmet(3)
- Yüzüak, Ercüment(3)
- Zhang, Hui(3)
Yayınlar
- MakaleAçık Erişim2023Rüzgâr Enerji Santrali (RES) Yer Seçimi için BWM-CBS Tabanlı Bir Yaklaşım: Tunceli Örneği
Konurhan, Zekeriya; Başaran, Erkin
Günümüz dünyasında fosil yakıtların yerine alternatif bir enerji kaynak arayışı oldukça popüler bir yaklaşımdır. Güneş panelleri ve rüzgâr enerjisi santralleri gibi yenilenebilir enerji kaynakları fosil yakıtların alternatifleri arasındadır. Rüzgâr enerjisi santralleri hem denizde hem de karada olmak üzere dünyanın birçok bölgesinde aktif olarak kullanılmaktadır. Türkiye’de de RES’ler özellikle 2000’lerin başından itibaren kullanılmaya başlamıştır. Türkiye’deki RES’ler daha çok Ege ve Marmara Bölgesinde yer almaktadır. Çalışma alanı olan Tunceli’de ise herhangi bir RES bulunmamaktadır. Bu çalışmanın temel amacı Tunceli için uygun RES alanlarını önermektir. Bu kapsamda Best-Worst yöntemi (BWM) CBS’ye entegre edilerek kullanılmıştır. BWM yöntemi ikili karşılaştırmaya dayanan Çok Kriterli Karar Verme (ÇKKV) yöntemidir. Çalışmada BWM modeli kullanılarak “topografya”, “sosyo-ekonomik”, “teknik” ve “lokasyon” olmak üzere dört ana kriter altında 16 kriter belirlenmiştir. Her bir kriter farklı disiplinlerden uzmanlar tarafından anket olarak değerlendirilmiş ve uygun yer seçimi için kullanılmıştır. 16 kriter için ayrı ayrı haritalar oluşturulmuş, kriterlerin açıklamaları yapılmış ve bu haritalar sonuç haritasında kullanılmıştır. BWM modeli kullanılarak tespit edilen kriter ağırlıkları CBS’ye entegre edilerek Tunceli için uygun RES kurulum alanları belirlenmiştir. Buna göre, Tunceli’nin güneydoğusunda yer alan Pertek ve Mazgirt çevresi ile Pülümür’ün kuzeyi ve Çemişgezek’in çevresinde fiziki coğrafya açısından uygun şartları sağlayan bazı alanlar RES kurulumuna elverişlidir.
AtıfOpenAlex5TR Dizin3
İncele - MakaleAçık Erişim2023Reclaim of Wrecked Bi-Te Based Materials In Peltier Modules In Thermopower Properties By Mechanical Milling
Yüzüak, Ercüment; Cetin, Mehmet; Yüzüak, Gizem Durak
We thoroughly evaluated the effects of various treatments on the structural and electrical properties of the two as-cast materials, “Sb-doping Bi-Te (p-type)” and “Se-doping Bi-Te (n-type)” which are frequently present in abandoned Peltier modules. To investigate the thermoelectric properties of Bi2Te3-based materials, waste alloys characterized by electrical conductivity using the hot-end method. Alloys were purified by performing arc melting on a water-cooled copper crucible in a vacuum of at least 10-3 mbar, with five times melting sessions to assure homogeneity. A single and long milling period of 144 hours is applied. After the compressing operation, the resulting discs with nanostructures were annealed for an hour at 600 K under vacuum conditions. The discs' structural properties were characterized using X-ray diffraction (XRD) and their surfaces and stoichiometries were determined using scanning electron microscopy with an energy dispersive feature. The Seebeck coefficient of the nanoparticle formed n-type Bi-Te based sample is -35.3 μV.K-1 and p-type Bi-Te based sample is 100 μV.K-1 (15% of mean error margin). It was found that a notable improvement was attained in comparison to the initial state with the addition of nanoparticles.
- MakaleAçık Erişim2023Self-Powered Mechanical Energy Sensor Application of SnO2/Ag and PMMA/ITO Nanocomposites via Triboelectric Effect
Yüzüak, Ercüment; Cetin, Mehmet; Yüzüak, Gizem Durak
The triboelectric nanogenerator is a state-of-the-art device for addressing the growing problem of meeting the world's ever-increasing energy needs by converting mechanical energy into electrical energy. Using the popular semiconductor SnO2 nanostructured thin films as a triboelectric layer over contact regions, as opposed to polymers with lesser performance, increases the output power and life time of nanogenerators. In order to design a triboelectric nanogenerator, deposited thin film SnO2 is used as a friction layer with Ag electrode after heat-treatment at 623 K with a contrary layer of PMMA poly (methyl-methacrylate) with ITO electrode. The structural and electrical properties were analyzed by using scanning electron microscopy (SEM), electro-impedance spectroscopy (EIS) and atomic force microscopy (AFM) measurements. The increased output power of the triboelectric nanogenerator is attributed to the nanoscale PMMA contact charge created by tunneling electrons in the SnO2/Ag nanocomposite thin film layer. Due to its proximity to the PMMA/ITO surface, the SnO2/Ag layer causes electron field emission, and tapping the SnO2/Ag layer may result in electron cloud overlap. Similar to a semiconductor/insulator interface, the Fermi level of SnO2 plays a crucial role in electron transport. The system efficiency stated as a touch detector in a conventional keyboard that generates its own power is revealed in part by an analysis of its operating state up to the 4V.
AtıfOpenAlex2İncele - MakaleAçık Erişim2023An integrated Bayesian Best-Worst Method and GIS-based approach for offshore wind power plant site selection: A case study in North Aegean and Marmara Sea (Türkiye)
Gul, Muhammet; Yucesan, Melih; Konurhan, Zekeriya
In today’s world, renewable energy sources are in great demand due to the negative ef- fects of fossil fuels on the environment. Wind power plants are an important renewable energy source alternative to fossil fuel consumption. Offshore wind farms established in coastal areas and seas are used effectively in many parts of the world. The wind power plants, especially in the Northwest region of Turkey and the Aegean coasts, constitute an important potential. This study selects suitable sites for offshore wind farms in the Marmara Sea and North Aegean Coasts of Turkey by integrating the Bayesian Best-Worst method (BWM) and GIS. Bayesian BWM improves the traditional BWM integrating the preferences of multiple experts. In the study, 17 sub-criteria were determined under four main criteria of “technical”, “socio-economic”, “environment,” and “location”. Ex- perts’ judgments through the filled enabled the criterion weights to be obtained. The criteria weights found using the Bayesian-BWM model were integrated into the GIS, and suitable locations for the offshore wind farm were determined. Accordingly, the study area off the coasts of Aliağa, Bozcaada, and Gökçeada on the North Aegean coast, and the part south of the Marmara Sea and the area around Kapıdağ Peninsula are sugges- ted as suitable areas for wind power plants.
AtıfOpenAlex7İncele - MakaleYalnız künye2023Scopus SJRQ4Development of a best-worst method based MCDM approach for solar power plant location selection: an application to Tunceli, Turkey
Aykac, Yunus Emre; Yucesan, Melih; Gul, Muhammet
Solar energy stands out with its increasing potential in the world. The decision to choose the location of a solar power plant is very important due to the investment return. In this study, a solar power plant site selection for Tunceli, Turkey is studied with a two-stage multi-criteria decision-making approach. In the first stage, the importance levels of the determined nine factors are obtained by the best-worst method (BWM). In the second stage, the most appropriate site is selected among the eight districts of Tunceli. As a result of the first stage, solar and fault line emerged as the most and least important factor, respectively. The second stage showed that Pertek district is the most suitable place. A comparative framework has been created including five different MCDM methods, which strengthens the final decision's accuracy and reveals whether each method's results are correlated.
AtıfScopus5OpenAlex3
İncele - Kitap BölümüYalnız künye2023A GIS-Based BWM Approach for the Location Selection of Solar Power Plant in Tunceli Province (Turkey)
Konurhan, Zekeriya; Yucesan, Melih; Gul, Muhammet; Rezaei, J; Brunelli, M; Mohammadi, M
The world has recently tended to turn to renewable energy sources due to the serious negative impact of fossil fuels on the environment. One of the top priorities for solar energy is the selection of the most suitable location of the solar power plant to be established. In this study, the most suitable solar power plant location selection for Tunceli, a province located in the eastern part of Turkey, is studied with an approach based on Geographic Information System (GIS) and the best-worst method (BWM). A weighting was performed using the BWM model for 16 sub-criteria under four the main criteria of “climatic conditions, geographical conditions, land conditions, and location (distance to crucial points)”. Afterward, maps were created for these criteria, and a 6-point scale in the legends of each map for each sub-criteria was applied. Finally, the most suitable locations were determined with GIS-based calculations.
AtıfScopus6WoS5OpenAlex7
İncele - MakaleAçık Erişim2023Theoretical and Practical Investigation of Stability Performance for Power Regulation in Hydroelectric Power Plants
Kahraman, Gökhan; Işık, Erdem
Hydroelectric power plants are the insurance of the interconnected system in order to provide fast energy to the system compared to other fossil fueled power plants. Hydroelectric power plants control the balance between the energy it supplies to the interconnected system and the pressurized water it uses with a system based on the fully automatic control principle. The quality of the energy supplied to the interconnected system depends entirely on this automatic control mechanism. In this study, mathematical models of the mechanisms that affect the automatic control system during the generation of energy in hydroelectric power plants are formed. Transfer functions of the obtained mathematical models are calculated by laplace transform. With the calculated transfer functions, the responses of the units of a hydroelectric power plant to the change of the amount of energy produced under different operating conditions are determined. The obtained data are compared with the actual conditions in a 1330 MW hydroelectric power plant with 8 Francis turbines. It is seen that the mathematical model and the turbine responses in real conditions are similar. In the calculations made at 115, 125, 135, 145 m. net head, the best stability conditions were obtained at 135 m. In addition, as a result of the calculations obtained under different operating conditions, ideal operating conditions are determined to minimize the fluctuations in energy production.
AtıfScopus2OpenAlex2İncele - MakaleYalnız künye2023Scopus SJRQ1A data-driven evaluating method on the defrosting effect of the air source heat pump system in Beijing
Guo, Yanhua; Shao, Shuangquan; Geng, Xudong; Li, Hao; Wang, Zhichao; Akkurt, Nevzat
The current demand-based defrosting initiation strategies of air source heat pumps (ASHPs) faces difficulty in achieving a balance between cost and robustness. Therefore, an efficient and innovative demand-based defrosting initiation strategy is proposed in this paper, based on the learned the degradation of heating capacity (DHC) method using data-driven model. Firstly, the DHC method is developed using the initially installed sensors without additional sensors to identify the frosty state. Subsequently, the fully connected neural network (FNN) model is established for predicting frosty state using field measured data from the ASHP system. Finally, the effectiveness of the defrosting initiation strategy is further validated through practical testing. The results demonstrate that the DHC method provides a reliable database for training the FNN model, resulting in an impressive accuracy of 91.43% for predicting the frosty state in the testing set. By adopting the innovative demand-based defrosting initiation strategies, the defrosting frequency, heating loss, and power consumption are respectively decreased by 66.3%, 2.1%, and 6.0% with the SCOP enhanced by 8.6% during a heating season. The promising results highlight that the proposed strategy effectively reduces costs while ensuring the efficiency of demand-based control.
AtıfScopus23WoS22OpenAlex27İncele - MakaleYalnız künye2023Scopus SJRQ2Numerical investigation of the effect of using louver baffles on thermal performance in solar air collectors
Tuğan, Volkan; Işık, Erdem
Conventional flat plate solar air collectors have advantages such as low cost and simple design. However, their thermal efficiency is lower than that of other designs. The thermal efficiency of these collectors can be increased by detailed examination of parameters such as the shape, size, arrangement and material of the air duct. In this study, it is aimed to improve the thermal efficiency of solar air collectors. The effect of louver baffles, which were not previously used in solar air collectors, on thermal efficiency was investigated numerically via computational fluid dynamics. Three different solar air collectors with flat plates, segmented baffles, and louver baffles were compared in terms of thermal efficiency. In addition, pressure drops in solar air collectors were investigated. The mass flow rate of the air in all collectors is assumed to be 0.04 kg/s. Analyzes were carried out between 09:00 and 16:00. The thermal efficiency values obtained during the day for solar air collectors with flat plate, segmented baffles and louver baffles are 27.66%–56.35%, 29.57%–58.82% and 30.09%–59.47%, respectively. The daily thermal efficiency values obtained for solar air collectors with flat plate, segmented baffles and louver baffles are 46.98%, 49.18% and 49.87%, respectively. The pressure drop for solar air collectors with flat plate, segmented baffles and louver baffles were found to be 4.62, 18.82 and 5.96 Pa, respectively. Based on the data obtained from this study, louver baffles are recommended for use in solar heating applications due to their high thermal efficiency and low pressure drop.
AtıfScopus5WoS5OpenAlex5İncele - MakaleYalnız künye2023Scopus SJRQ1Energy, exergy and cost analysis of different hemispherical solar distillers: A comparative study
Hadi Attia, Mohammed El; Hussein, Ahmed Kadhim; Radhakrishnan, Ganesh; Vaithilingam, Sivakumar; Younis, Obai; Akkurt, Nevzat
The experimental study of the results of reflective aluminum foils, metal sheets, and phosphate granules on the productivity and efficiency of hemispherical solar stills was given throughout this work under the solar conditions of the city of El-Oued (Algeria). Solar stills were designed, manufactured, and tested in August 2020. A standard hemispherical solar still was made of wood and coated with black silicon. It was considered a traditional solar still. Although it was compared to traditional solar stills, it was improved by covering its side walls with reflective aluminum foil, zinc metal sheets, and copper sheets. It had been found that the productivity of the modified still was 8.67%, 29.08%, and 42.35%, respectively, on top of that of the traditional solar still. This could be due to the activity of the foils and metals, which reflect more radiation and store energy, increasing the temperature of the salt water in the basin. In the second experiment, three modified solar stills in line with aluminum foil and phosphate granules (30 g/L), zinc metal sheet and phosphate granules, and copper metal sheet and phosphate granules were collectively used. It had been found that the productivity of the modified solar still with aluminum foil and phosphate granules (the improvement rate is 30.61%) was on the far side of that with zinc metal sheets and phosphate granules (the improvement rate is 49.961%) and copper metal sheets and phosphate granules (the improvement rate is 62.24%).
AtıfScopus37OpenAlex34İncele - MakaleAçık Erişim2023Scopus SJRQ1Analysis of unsteady thermo-solutal MoS2-EO Brinkman electro-conductive reactive nanofluid transport in a hybrid rotating Hall MHD generator
Shamshuddin, M.D.; Bég, O. Anwar; Akkurt, Nevzat; Leonard, Henry J.; Bég, Tasveer A.
MHD rotating generators offer a plausible renewable energy mechanism. New designs are emerging in which nanotechnology is contributing. Such systems are increasingly deploying more complex functional fluid materials such as base fluids containing magnetic nanoparticles which constitute electromagnetic nanofluids and can be tuned to enhance efficiencies. Motivated by these developments, a mathematical model is presented for the combined effects of Hall current, heat source, chemical reaction and radiative flux on the unsteady rotating thermo-solutal magnetohydrodynamic transport of a Molybdenum disulphide (MoS 2)-EO oil electroconductive Brinkman nanofluid to study the boundary layer characteristics in the vicinity of the side wall of an MHD generator system. The governing dimensional conservation equations are scaled using appropriate transformations into a system of dimensionless coupled partial differential equations. Under appropriate initial and boundary conditions, solutions are derived using the Laplace Transform Method (LTM) and complex variables. The physical impacts of the magnetic, nanoscale, thermal and species control parameters on primary and secondary velocity, temperature and concentration are visualized graphically. The judicious doping of the base fluid with MoS 2 nanoparticles is shown to achieve superior thermal performance for MHD rotating energy generators.
AtıfScopus38OpenAlex24İncele - MakaleAçık Erişim2023Scopus SJRQ2Investigation on application of plate-tube evaporative condensating technology for data centres in the northwest of China
Wu, Xueyuan; Shao, Shuangquan; Akkurt, Nevzat
The rapid development of data center leads to a rapid increase in energy consumption. In this paper, the plate and tube evaporative condenser is proposed for the water-cooled chiller and the data center cooling system to improve the energy efficiency in hot and dry summer and avoid icing in cold winter. The chiller can operate in the wet mode for compressor refrigeration and the dry mode for free cooling with the coefficient of performance (COP) of 5.2 in wet mode and up to 33.3 in dry mode. Furthermore, the system is applied in a data center in Ulumiqi, which is located in the dry and cold region and its ambient air temperature can vary from −32 °C to 45 °C throughout the year. The actual operation results show that the power usage effectiveness (PUE) value of the whole data centre is 1.349 in June, 1.229 in December, and 1.320 as the annual average, which is stable and efficient for five consecutive years. These results ensure the proposed system is an important technical solution for energy saving and emission reduction in data centres in cold regions.
AtıfScopus9WoS5OpenAlex8İncele - MakaleYalnız künye2023Scopus SJRQ1Carbide slag recycling to fabricate shape-stable phase change composites for thermal energy storage
Xiong, Yaxuan; Wang, Huixiang; Ren, Jing; Nevzat, Akkurt; Xu, Qian; Nie, Binjian; Li, Chuan; Ding, Yulong
The mining and processing of traditional skeleton materials inevitably generates carbon emissions and pollutes the surrounding environment. To make full use of industrial solid waste, this work innovatively used carbide slag as skeleton material and Na2CO3 as phase change material (PCM) to fabricate shape-stable phase change composites (SSPCCs) via the cold-compression & hot-sintering method. Seven SSPCCs were fabricated with different mass ratios of carbide slag to Na2CO3. Then, the thermal energy storage (TES) performance, mechanical property, micromorphology, chemical compatibility as well as thermal cycling stability were investigated. The results showed that the carbide slag could combine with Na2CO3 to fabricate SSPCCs; Sample CN5 achieved the optimal performance with the mass ratio 52.5:47.5 of carbide slag to Na2CO3; Sample CN5 achieved a TES density of 993 J/g in the range of 100 to 900 °C, a compressive strength of 22.02 MPa and a maximal thermal conductivity of 0.62 W/(m·K); Both carbide slag and Na2CO3 were distributed uniformly in sample CN5, while good thermal stability after the 100 heating/cooling cycles and good chemical compatibility between the carbide slag components and the Na2CO3 were observed.
AtıfScopus34OpenAlex30İncele - MakaleYalnız künye2023Scopus SJRQ1Heat loss optimization and economic evaluation of a new fourth generation district heating triple pipe system
Chen, Xingli; Ren, Ling; Zheng, Qiang; Yang, Gang; Akkurt, Nevzat; Liu, Lin; Liu, Zhiwei; Qiang, Yujie; Yang, Huachao; Xu, Qian
In response to the heat loss caused by the temperature difference between the heating pipes and external environment during the pipe transportation, heat contradiction between the total heat loss of the piping system and heat transfer between tubes, as well as economic balance between the cost of heat loss and cost of material loss. Based on TOTS (Two-supply/One-return, triple pipe structure) heat loss theory of the fourth-generation district heating system, this paper optimizes structure of pipes by setting dimensionless characteristic parameters θ and β. Finally, a mathematical model is proposed to calculate economic efficiency of pipeline network by considering the cost of initial construction material loss and operation heat loss of the pipe. Results show that, from energy perspective, comprehensive heat as system energy consumption evaluation index is positively correlated with θ, decreases first and then increases as β increases. Total heat loss of system dominates comprehensive heat. Lowest comprehensive heat of system is 18.12 w/m for θ of 0.1945 and β of 0.0739. From economic perspective, total system loss cost as system economic evaluation index is positively correlated with both θ and β. Total system heat loss cost dominates total system loss cost. Lowest total system loss cost is $29.39/m for θ of 0.1945 and β of 0.0509.
AtıfScopus16OpenAlex20İncele - MakaleYalnız künye2023Scopus SJRQ1Latent heat thermal energy storage in a shell-tube design: Impact of metal foam inserts in the heat transfer fluid side
Ghalambaz, Mehdi; Sheremet, Mikhail; Raizah, Zehba; Akkurt, Nevzat; Ghalambaz, Mohammad
The improvement of heat transfer in latent heat thermal energy storage (LHTES) system is a crucial task. In the current study, the impact of diverse metal foam (MF) layer arrangements on heat transfer fluid (HTF) within a shell-tube LHTES is explored. Six distinct cases (A-F) with varied MF coverage percentages and layer dimensions were assessed. The local thermal non-equilibrium model was utilized to take into account the PCM and MF temperatures. The finite element method was used for solving the partial differential equations. The impact of MF configurations and inlet pressures (250 Pa, 500 Pa, and 750 Pa) on the thermal energy storage/release was addressed. Cases A-C, featuring a 50 % MF concentration, exhibit shorter melting times than Cases D–F, with decreasing MF concentrations. A higher MF concentration improves the melting process due to increased thermal conductivity and lower thermal resistance on the HTF side. Cases D–F, with a centralized MF layer and decreasing concentrations from 25 % to 6.25 %, display progressively shorter melting times, suggesting that a lower MF concentration leads to more efficient melting. Solidification times also decrease with increasing inlet pressures across all cases. Reynolds numbers, influenced by average HTF tube outlet velocity, vary substantially across cases and inlet pressure differences. Cases A-C demonstrate similar Reynolds numbers for each inlet pressure difference, while Cases D–F show a more pronounced increase in Reynolds numbers as the MF layer is reduced and flow resistance drops. Cases A (50 % MF layer) and F (6.5 % MF layer) provide the quickest charging and discharging times due to their unique combination of MF layer properties and inlet pressures. The study highlights the need to consider MF layer composition and inlet pressure when designing optimal LHTES systems for efficient energy storage/release.
AtıfScopus11WoS10OpenAlex11İncele - MakaleAçık Erişim2023Scopus SJRQ3Rotor Field-Oriented Control of Doubly Fed Induction Generator in Wind Energy Conversion System
Omac, Zeki; Erdem, Irfan
In this study, robust and high-performance vector control of a rotor side converter (RSC) was performed for stability and efficient operation doubly fed induction generator (DFIG) based on the variable speed wind turbine (VSWT). The mathematical model of the DFIG is simulated in the computer. Amplitude and frequency of the voltage in the DFIG were controlled for different values of load and variable speeds. In the experimental study, a DFIG-based wind turbine system was set up in the laboratory. The field position of the stator was detected from stator voltages by a phase-locked loop (PLL) circuit. The rotor position was measured with an incremental encoder connected to the rotor shaft of the DFIG. The angular position of the slip was calculated by the difference between the rotor and the stator field positions. The frequency and amplitude of rotor currents were determined with the angular position of slip. To generate output voltages of converter feeding rotor windings, the space vector pulse width modulation (SVPWM) technique was used. In the experimental study, the RSC was controlled with the DS1103 board. The prepared experiment set was tested at different operating speeds.
AtıfScopus4WoS3OpenAlex4İncele - MakaleAçık Erişim2022Scopus SJRQ4Biyo-hidrometalurjik yöntemler ile kullanılmış vanadyum katalizörlerden vanadyumun geri kazanımı ve pilot ölçekli uygulamalar için tekno-ekonomik analiz
Erüst, Ceren
Sülfürik asit üretiminde katalitik indirgemeyi sağlayan vanadyum katalizörlerinin yaygın kullanımı, tehlikeli atık olarak kabul edilen kullanılmış katalizörlerin zamanla daha da artmasına neden olmaktadır. Kullanılmış vanadyum katalizörler (KVK), yüksek oranda SiO₂ ve ağır metal içeriğinin yanında kritik metal listesinde yer alan vanadyumu da içermektedir. Döngüsel ekonomi politikası uygulamalarına yönelik artan talep, bu atıklardan vanadyumun kazanımı için tekno-ekonomik açıdan uygun bir yol geliştirmeyi gerektirmektedir. Bu çalışmada, kimyasal liç (1 M sülfürik asit ve %1 h/h hidrojen peroksit) ve biyoliç (Acidithiobacillus ferrooksidans, Acidithiobacillus thiooxidans ve Leptospirillum ferrooxidans içeren karışık bakteri kültürü) yöntemleri kullanılmış ve KVK’lardan vanadyum kazanımı değerlendirilmiştir. Katalizörlerde bulunan vanadyum, hidrometalurjik ve biyohidrometalurjik yöntemlerle yüksek verimle (%96,8 ve %97,1) kazanılmıştır. Geliştirilen modelleme de biyohidrometalurjik yöntemin yatırım maliyetinin 3,8 yılda geri karşılanacağı ve geri ödeme yüzdesi %89,32 olarak öngörülmüştür. Hidrometalurjik yöntemde ise, yatırım maliyetinin 1,2 yılda karşılanacağı ve geri ödeme yüzdesinin %80,3 olduğu belirlenmiştir. Bu sonuçlar hidrometalurjik yaklaşımın daha hızlı, biyohidrometalurjik yaklaşımın ise daha ekonomik bir yöntem olduğunu göstermiştir.
- MakaleAçık Erişim2022Çok Katmanlı Algılayıcı Algoritması, Korelasyon Tabanlı Özellik Seçme Yöntemi ve Eğri Uydurma Tekniği ile Türkiye’ de Toplam Elektrik Tüketiminin Tahmin Edilmesi
Akmaz, Düzgün
Elektrik tüketiminin tahmin edilmesi, güç sistemlerinin planlanması ve işletilmesinde önemli bir rol oynar. Bu yüzden bu çalışmada Çok Katmanlı Algılayıcı Algoritması (ÇKAA), Korelasyon Tabanlı Özellik Seçme Yöntemi (KTÖSY) ve Eğri Uydurma (EU) teknikleri ile Türkiye’ de toplam elektrik tüketimini tahmin eden bir model geliştirilmiştir. 2013-2018 yılları arası veriler ÇKAA, KTÖSY ve EU modelini oluşturmak için kullanılırken 2019-2020 yıllarındaki veriler ise modelin başarısını test etmek için kullanılmıştır. Yazılım sonuçları yöntemin geçmiş yıllardaki toplam elektrik tüketimini tahmin etmede başarılı olduğunu göstermiştir. Aynı zamanda oluşturulan model ile 2024 yılına kadar Türkiye’ deki toplam elektrik tüketimi de tahmin edilmiştir.
AtıfOpenAlex2TR Dizin1İncele - MakaleAçık Erişim2022The effect of using phase change materials and examining the aspect ratio in an air-cooled system of a plate battery connected to a solar system
Akkurt, Nevzat
Lithium-ion batteries are widely used in the electronics industry to store electrical energy. One of the challenges with these batteries is that they heat up during operation, which can damage the battery. For this reason, this paper simulates the cooling process of a plate-type (BTP) lithium-ion battery pack. To control the temperature of the battery (T-B), a laminar air flow and a phase change material (PCM) are used. The PCM is placed in a heat sink around the battery. This evaluation is performed temporarily for four different dimensions of the PCM pack. The hot outlet of this system is used to provide the thermal energy required for a small residential building (THE) at a mild temperature. The BTP was also simulated using COMSOL. The results show that the use of larger heat sinks can increase the maximum (MAX) and average (AVE) temperature of the battery. The minimum T-B occurs at different times for the smaller PCM heat sinks. Also, when using a heatsink with a larger PCM volume, it takes longer for the PCM to fully solidify. A BTP with 5 or 50 battery cells can provide up to 3% or 30% of the THE required for the building.
- MakaleAçık Erişim2022Investigation of an Outer Rotor In-Wheel Switched Reluctance Motor for Electric Vehicles by Finite Element Method
Omaç, Zeki
The demand of fossil fuel vehicles has decreased due to carbon emissions. Recently, electric vehicles (EV) with electric motor propulsion have gotten attention due to their zero carbon emissions and high efficiency. In this study, an outer rotor in wheel switched reluctance motor (IWSRM) with 18 poles on the stator and 24 poles on the rotor, designed for the propulsion of electric vehicles, is investigated in two-dimensional Finite Element Method (FEM). The magnetic field distributions of IWSRM for different rotor positions at nominal current are obtained. Then, the torque and phase inductance are calculated. As a result, the designed IWRSM provided low torque.
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