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Fotovoltaik (FV) modüller, üzerine düşen güneş ışınlarından elektrik üretimini sağlayan ve yüzeyinde birden çok FV hücre bulunan yapılardır. FV hücreler, sadece direkt gelen ışınları değil, yüzeye gelen tüm ışığın belirli dalgaboyu aralığını enerji üretimi için kullanabilirler. FV modüller, yapıları gereği sıcaklıkları, ortam sıcaklığına kıyasla daha fazla olmakta ve bu durum FV hücrelerin elektriksel verim ve güç üretim düşümüne neden olmaktadır. Bu sebeple, FV modüllerde depolanan ısı enerjisinin dışarıya transferi konusunda akademik çalışmalar son yıllarda ivme kazanmıştır. Örneğin, FV modüllerden ısı enerjisi elde edilerek sıfır enerji tüketim hedefi altında konutların ısıtma yükü karşılanmakta ve ilerleyen çalışmalar ile birlikte sistem/enerji verimi arttırılmaktadır. Bu çalışma, FV modüllerin ısı iletim performansının geliştirilmesine yönelik polimer esaslı takviye malzemelerin kullanımı ile oluşturulan kompozit yapılar incelenerek, FV modülde depolanan ısı enerjisinin azaltılmasını hedef almıştır. Bu amaçla, takviye malzemeler araştırılmış ve karbon, cam elyaf, aramid (kevlar) takviye malzemelerinin iki farklı parametre altında araştırılması uygun görülmüştür. Bu iki parametre, herbir takviye malzemenin farklı tabaka kalınlıklarındaki ve birbirleri ile oluşturduğu hibrit yapıdaki sahip oldukları ısı iletim performansını araştırmaktadır. Araştırma sonucunda karbon elyaf takviye malzemesi ile oluşturulan yapının 6,51 W/mm2 ısı akısı ile birlikte optimum yapı olduğu elde edilmiştir. Isı iletim performansında karbon elyafı cam elyaf (0,013 W/mm2) ve aramid (4.10-4 W/mm2) takip etmiştir. Bu araştırma polimer kompozit malzemeler ile lamine edilmiş FV modül ve konvansiyonel tip FV modül arasındaki ısı akısı farkını 0,0242 W/mm2 olarak elde ederek FV modüllerden elde edilebilen ısı enerjisinin arttırımına katkıda bulunmuştur., Photovoltaic (PV) modules are structures that produce electricity from the sun's rays falling on them and have more than one PV cell on their surface. PV cells can use not only direct rays, but also a certain wavelength range of all light coming to the surface for energy production. Due to their nature, PV modules have a higher temperature compared to the ambient temperature, which causes a decrease in the electrical efficiency and power generation of the PV cells. For this reason, academic studies on the transfer of heat energy stored in PV modules to outside have gained momentum in recent years. For example, by obtaining heat energy from PV modules, the heating load of the houses is met under the target of zero energy consumption, and the system/energy efficiency is increased with further work. This study aimed to reduce the heat energy stored in the PV module by examining the composite structures formed using polymer-based reinforcement materials to improve the heat conduction performance of PV modules. For this purpose, reinforcement materials were investigated, and it was found appropriate to investigate carbon, glass fiber, aramid (Kevlar) reinforcement materials under two different parameters. These two parameters investigate the heat conduction performance of each reinforcement material in different layer thicknesses and in the hybrid structure formed with each other. As a result of the research, it has been obtained that the structure formed with carbon fiber reinforcement material is the optimum structure with a heat flux of 6.51 W/mm2. In heat conduction performance, carbon fiber was followed by glass fiber (0.013 W/mm2) and aramid (4.10-4 W/mm2). This research contributed to the increase of the heat energy that can be obtained from PV modules by obtaining the heat flux difference between the PV module and the conventional type of PV module laminated with polymer composite materials as 0.0242 W/mm2.

Worldwide need for renewable energy sources increases significantly with the drastic negative greenhouse effects of climate change. This study considers a water-cooled hybrid thermo-electric panel (PV/T) which contributes to better harvesting of solar energy. A numerical CFD model was developed for power generation of a standard PV panel as well as for a water-based PV/T system laminated with polymer matrix composite (PMC) materials, and user-defined functions (UDFs) were developed and integrated with the CFD model to implement exact boundary conditions. Experimentation under daily weather conditions was carried out in order to validate the numerical CFD model by measuring the surface temperatures of PV and PV/T systems as well as the temperatures of the water inlet and outlet of the cooling system. The results show that the maximum and minimum deviations of the surface temperature between numerical and experimental studies matched well compared with the studies performed in the literature. Moreover, the numerical model had a rapid response to temperature changes of PV and PV/T modules under sudden weather changes (cloudy/sunny). It was shown that the electrical efficiency of the cooled PV/T module can achieve 20.8% in addition to a thermal efficiency of 53.5%. The current study is a validation of the performance of polymer composite laminated water-cooled PV/T systems under daily weather conditions.

In this study, the natural frequencies of Solaris 10 Solar Car’s 2018 and 2019-Model wheels were determined experimentally by the impact hammer test under free-free boundary conditions and the results were compared with the natural frequency results obtained using ANSYS FEA software. Comparing the numerical and experimental vibration analysis, a maximum percent error of 7.46% was observed. The 7th and upper mode frequencies of 2018 and 2019 wheel models were shown to be above 200 Hz and the experimental results were validated. After expressing the mode shapes in the ANSYS-Modal Analysis, a parametric study was performed for the 2019 wheel model using the ANSYS- Parametric Design. As a result of the parametric design, the mass of the 2019 wheel model was decreased by 6.5% while maximum equivalent von Mises stress was decreased by 2%. Thus, a lighter wheel design was obtained with ANSYS FEA software and maximum equivalent von Mises stress value was achieved to be below pre-defined limit of 120 (MPa)., Bu çalışmada, dönmeyen lastiksiz Solaris 10 güneş arabası jantının 2018 ve 2019 modellerinin doğal frekansları, serbest sınır koşulları altında darbe çekici testi ile deneysel olarak belirlenmiş ve sonuçlar ANSYS Sonlu Elemanlar Analiz yazılımında elde edilen doğal frekans sonuçları ile karşılaştırılmıştır. Sayısal ve deneysel olarak elde edilen doğal frekans sonuçları karşılaştırıldığında, maksimum yüzde 7.46 hata elde edilmiştir. Deneysel olarak elde edilen sonuçlar doğrulanmış ve 2018 jant modeli ile 2019 jant modelinin 7. mod frekans ve üstü frekanslarının 200 Hertz'in üstünde olduğu gösterilmiştir. ANSYS- Modal Analiz modülünde gözlemlenen mod şekilleri, yüksek genlik oluşturabilecek doğal frekanslar için gösterilmiştir. 2019 Jant modeli için parametrik CAD modeli kullanılarak bir tasarım optimizasyonu çalışması gerçekleştirilmiştir. Tasarım optimizasyonu sonucunda 2019 jant modelinin kütlesi % 6.5 azalırken, maksimum eşdeğer von Mises gerilmesi % 2 azaltılmıştır. Böylelikle, ANSYS Sonlu elemanlar analizi yazılımında parametrik çalışma ile daha hafif bir jant elde edilmiş ve maksimum eşdeğer von Mises gerilmesi 120 MPa'nın altında kalması sağlanmıştır.

© International OCSCO World Press. All rights reserved.Purpose: Use of aluminium alloys in critical parts of a vehicle is common since they can combine the two important properties of a material those are being strength and lightweight. The aim in this research is to guide to design process of a wheel with taking example of an electric race vehicle implementation. Design/methodology/approach: In this study, the fatigue strengths of wheels produced for a two-person racing electric vehicle (Demobil09) are evaluated by calculating maximum distortion energy criterion (Von Mises) with Finite Element Analysis. Findings: Aluminium alloy wheels are crucial safety related components and are subjected to static and dynamic loads directly. Using FEA results, the weight and equivalent stress of the wheel are both reduced. So, the energy consumption is also decreased. Modal frequencies of the wheel models are determined. Research limitations/implications: In this paper, the materials analysed are AL6063 T6 and Al5083 aluminium alloys. Different materials can be analysed in future works. Practical implications: This paper is focusing on how to reduce the energy consumption of a two-person electric vehicle concentrating on reducing the weight of vehicle wheels. The vehicle is more technological than mass production cars since it is an electric race car which uses a hub motor, the body and chassis are produced using carbon polymer composites and all electronic units are designed and produced. Although its specialities it has homologated safety equipment like seats and safety belts. Originality/value: All boundary conditions must be analysed in details and a strength analysis must be conducted during design of the wheels for different load cases to ensure the strength of a wheel while keeping the weight as low as possible. In this complex process, this paper can give some clues to designers for strengths and weights of the designs since three different wheel forms are evaluated for reducing energy consumption of the vehicle.

The increasing trend of the energy consumption of humanity has brought forward the efficient use of current energy resources and seeking for the adaptation of renewable energy resources. Integration of renewable energy into transportation, on the other hand, has crucial importance as it reduces the emissions in the urban regions and increases the life quality by reducing the noise in solar-powered electric vehicles. Solar-powered vehicles, automobiles or planes, with photovoltaic panels (PVPs) are widely in use for decades. However, there are several aspects, such as electrical conversion and storage efficiencies, that should be improved. It is known that increasing the temperature of the PVPs adversely affects both the panel lifetime and electrical conversion efficiency. In this study, a 3DCFD model of a solar-powered racing car is developed in ANSYS-FLUENT to investigate the power outputs of the PVPs that are placed on different positions of the vehicle under various velocities, i.e., 30-120 km/h, and solar irradiations, i.e., 300-900 W/m(2).