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Öğe 3B yazıcılarda kullanılan farklı tip ekstüderlerin ANSYS programı ile termal analizlerinin gerçekleştirilmesi(Düzce Üniversitesi Fen Bilimleri Enstitüsü, 2022) Demir, Hasan; Coşgun , Atıl EmreBu çalışmanın amacı, 3B yazıcılarda ticari olarak kullanılan J-Head ekstrüder ve Volcano ekstrüderlerin ANSYS sonlu elemanlar yazılımı ile modellerin kararlı hal termal analizlerini gerçekleştirmek, modellerin eksiklikleri ve birbirlerine göre üstünlüklerini belirlemektir. Modellerin tasarımsal farklılıkları ve geometrik özellikleri farklı termal davranışlar göstermesine neden olmaktadır. Başlangıç koşulları ve sınır şartları her iki model için aynı olması sağlanmış, böylelikle diğer değişkenlerin sabit olmasına bağlı olarak tasarımların termal analizleri ön plana çıkarılmıştır. Termal analiz ile modellerin tasarımlarının baskı malzemesinin füzyonu üzerindeki etkileri incelenmiştir. Analiz sonuçları, modellerin avantaj ve dezavantajlarını ortaya koymuş ve gelecekte yapılabilecek yeni tasarımlar için bilgi kaynağı oluşturmuştur.Öğe A Review of Traditional and Advanced MPPT Approaches for PV Systems Under Uniformly Insolation and Partially Shaded Conditions(Multidisciplinary Digital Publishing Institute (MDPI), 2025) Endiz, Mustafa Sacid; Gökkuş, Göksel; Coşgun, Atıl Emre; Demir, HasanSolar photovoltaic (PV) is a crucial renewable energy source that converts sunlight into electricity using silicon-based semiconductor materials. However, due to the non-linear characteristic behavior of the PV module, the module’s output power varies according to the solar radiation and the ambient temperature. To address this challenge, maximum power point tracking (MPPT) techniques are employed to extract the maximum amount of power from the PV modules. This paper offers a comprehensive review of widely used traditional and advanced MPPT approaches in PV systems, along with current developments and future directions in the field. Under uniform insolation, these methods are compared based on their strengths and weaknesses, including sensed parameters, circuitry, tracking speed, implementation complexity, true MPPT, accuracy, and cost. Additionally, MPPT algorithms are evaluated in terms of their performance in reaching maximum power point (MPP) under partial shading condition (PSC). Existing research clearly demonstrates that the advanced techniques exhibit superior efficiency in comparison to traditional methods, although at the cost of increased design complexity and higher expenses. By presenting a detailed review and providing comparison tables of widely used MPPT techniques, this study aims to provide valuable insights for researchers and practitioners in selecting appropriate MPPT approaches for PV applications.Öğe Application of thermal energy harvesting from photovoltaic panels(MDPI, 2022) Demir, HasanThis paper describes a newly developed system for harvesting thermoelectric energy from photovoltaic panels. This system helps to power monitoring systems for photovoltaic panels (PVs) in locations where there is no energy source using waste thermal energy from PVs exposed to the sun’s rays. In the study described here, the thermal energy from a PV panel was captured and transferred to a thermoelectric generator (TEG). A temperature gradient was created by reducing the temperature using an aluminium heat sink in ambient weather conditions. This temperature gradient was used to generate electricity via two TEGs. In field tests carried out in April, in Aksaray province in central Turkey, the maximum temperature gradient due to solar radiation was measured as 21.08 °C. The harvested energy was increased to a usable level of 4.1 V using a DC-to-DC converter and stored in a li-ion rechargeable battery. The maximum charge current level of the battery was 147 µA. The maximum harvested energy was 458.64 mW, and a stable level of around 350 mW was achieved. The experimental operation of the prototype system was carried out in stable weather conditions; however, weather and climatic conditions greatly affect levels of energy harvested as a result of changing temperature gradients. The energy obtained with the prototype may reduce the battery maintenance costs of PV monitoring systems and lead to the development of new such systems which cannot presently be used due to a lack of energy.Öğe Investigating the Effect of Albedo in Simulation-Based Floating Photovoltaic System: 1 MW Bifacial Floating Photovoltaic System Design(Multidisciplinary Digital Publishing Institute (MDPI), 2024) Coşgun, Atıl Emre; Demir, HasanPhotovoltaic (PV) modules have emerged as a promising technology in the realm of sustainable energy solutions, specifically in the harnessing of solar energy. Photovoltaic modules, which use solar energy to generate electricity, are often used on terrestrial platforms. In recent years, there has been an increasing inclination towards the installation of photovoltaic (PV) modules over water surfaces, including lakes, reservoirs, and even oceans. The novel methodology introduces distinct benefits and complexities, specifically pertaining to the thermal characteristics of the modules. In order to accomplish this objective, a photovoltaic (PV) module system with a capacity of 1 MW was developed as a scenario in the PVsyst Program. The scenario simulation was conducted on the Mamasın Dam, situated in the Gökçe village within the Aksaray province. To conduct the efficiency analysis, a comparative evaluation was conducted between bifacial and monofacial modules, which were installed from above the water at 1 m. The comparison was made considering two different types of modules. Additionally, the albedo effect, water saving amount, and CO2 emissions of the system were also investigated. Albedo measurements were made in summer when the PV power plant will operate most efficiently. As a result of the simulations, it was found that bifacial modules produce 12.4% more energy annually than monofacial modules due to the albedo effect. It is estimated that PV power plant installation will save 19,562.695 and 17,253.475 tons of CO2 emissions in bifacial and monofacial systems, respectively.Öğe Path planning for 3 degree of freedom (RRR) robot and its application(Aksaray Üniversitesi Fen Bilimleri Enstitüsü, 2020) Demir, Hasan; Tolun, Mehmet ReşitBu çalışmada, 3 serbestlik derecesine sahip RRR robotun yörünge planlaması yapılmış ve 3d yazıcı ile üretilen model robot kol üzerinde uygulanmıştır. Yörünge planlaması yapılırken genetik algoritmalar kullanılarak zaman optimizasyonu yapılmıştır. Model olarak ilk üç eklemin Kartezyen uzayda konumu etkilemesi nedeniyle üç eklemi de döner eklem olan RRR yapıdaki robot kol kullanılmıştır. Robot kolun öncelikle ileri kinematik analizi yapılmıştır. İleri kinematik analiz yöntemi olarak en çok kullanılan analiz yöntemi olan Denativ-Hartenberg yöntemi seçilmiştir. İleri kinematik analiz sonucunda elde edilen bilgiler ile ters kinematik analiz yapılmıştır. Ters kinematik analiz sonucunda model robotun Kartezyen uzayda bir noktaya ulaşması için gerekli olan eklem değişkenlerini elde edilmiştir. Kinematik analizler robotun eklem uzayında yörünge planlamasını yapmak üzere gerçekleştirilmiştir. Robot kolun yörünge planlaması yapılırken hareketlerini en kısa sürede tamamlaması için genetik algoritmalar kullanılarak zaman optimizasyonu yapılmıştır. Eklem uzayında yörünge planlama sonucunda her bir eklem için elde edilen hız ve ivme denklemleri optimizasyonda amaç fonksiyonları olarak kullanılmıştır. Amaç fonksiyonunun sınırlarını robot kolun eklemlerinde kullanılan servo motorların hız ve ivme değerleri oluşturmuştur. Optimizasyon sonucunda her bir eklemin hareketini en kısa zamanda tamamlayabileceği süreler bulunmuştur. Model robot kol 3d yazıcıda üretilmiş ve deney seti oluşturulmuştur. Optimizasyon sonucunda elde edilen veriler deneysel çalışmalardan elde edilen veriler ile karşılaştırılmıştır. Bu çalışmanın sonuncunda genetik algoritmalar kullanılarak zaman optimizasyonu yapılmış ve her hangi bir robota uygulanabilecek hareketi en kısa sürede tamamlayan bir model oluşturulmuştur.Öğe Simulation and forecasting of power by energy harvesting method in photovoltaic panels using artificial neural network(Elsevier Ltd, 2024) Demir, HasanHeat is an important efficiency reducing factor in photovoltaic systems. Although many studies in the literature are related to the removal of waste heat from photovoltaic panels, the disadvantages such as installation and maintenance of cooling systems should not be forgotten. A study has shown that with a new approach, energy can be produced with the method of energy harvesting from waste heat. The results of the study were limited to a geographical region and climatic conditions in Aksaray, Turkey. In this article, the results of the study, which was limited to a region, were extended using the finite element method analysis and the artificial neural network model. Ten different cases were determined and temperature gradient was found by finite element analysis. The forecasting algorithm was developed with artificial neural network and estimates the harvestable power based on the temperature gradient. The accuracy of the algorithm was tested with the MSE and nRMSE statistical metrics which were calculated as 59.1423 mW and 13.6189 %, respectively. The training data accuracy of the network was 0.93987 and the combined accuracy was 0.94364. The results of this study are important to be a reference for researchers who want to establish a photovoltaic panel energy harvesting system.Öğe The effect on energy efficiency of Yttria-Stabilized Zirconia on brass, copper and hardened steel nozzle in additive manufacturing(MDPI, 2022) Demir, Hasan; Coşgun, Atıl EmreThis study aimed to investigate if a thermal barrier coating (TBC) affected the energy efficiency of 3D printers. In accordance with this purpose, the used TBC technique is clearly explained and adapted to a nozzle in a simulation environment. Brass, copper, and hardened steel were selected to be the materials for the nozzles. The reason for the usage of a thermal barrier coating method is that the materials are made with low thermal conductivity, which reduces the thermal conductivity and energy losses. Yttria-stabilized zirconia was used to coat material on brass, copper, and hardened steel. To prevent temperature fluctuations, yttria-stabilized zirconia together with a NiCRAl bond layer was used and, thus, heat loss was prevented. Additionally, the paper addressed the effects of the coating on the average heat flux density and the average temperature of the nozzles. In addition, by means of the finite element method, steady-state thermal analyses of the coated and uncoated nozzles were compared, and the results show that the thermal barrier coating method dramatically reduced energy loss through the nozzle. It was found that the average heat flux was reduced by 89.4223% in the brass nozzle, 91.6678% in the copper nozzle, and 79.1361% in the hardened steel nozzle.Öğe The effects on thermal efficiency of yttria-stabilized zirconia and lanthanum zirconate-based thermal barrier coatings on aluminum heating block for 3D printer(MDPI AG, 2021) Demir, HasanFused filament fabrication is an important additive manufacturing method, for which 3D printers are the most commonly used printing tools. In this method, there are many factors that affect the printing quality, chief among which is temperature. The fusion temperature of the material is created by an aluminum heating block in the extruder. Stability and a constant temperature for the aluminum heating block are inevitable requirements for print quality. This study aims to use the thermal barrier coating method to increase the thermal efficiency and stability of the aluminum heating block by reducing heat loss. Furthermore, it aims to perform steady-state thermal analysis using finite element analysis software. The analyses are carried out in stagnant air environment and at the printing temperature of acrylonitrile butadiene styrene material. In order to examine the effects of different coating materials, blocks coated with two different coating materials, as well as uncoated blocks, were used in the analyses. The coating made with yttria-stabilized zirconia and pyrochlore-type lanthanum zirconate materials, together with the NiCRAl bond layer, prevent temperature fluctuation by preventing heat loss. The effects of the coating method on average heat flux density, temperature distribution of blocks, and temperature distribution of the filament tube hole were investigated. Additionally, changes in flow velocity were determined by examining the effects of the thermal barrier coating method on temperature distribution. The average heat flux density in the coated blocks decreased by 10.258%. Throughout the investigation, the temperature distributions in the coated blocks became homogeneous. It was also observed that both coating materials produce the same effect. This article performs a steady-state thermal analysis of a conventional model and thermal-barrier-coated models to increase print quality by reducing heat loss from the aluminum heating block.
