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Tests of hail simulation and research of the resulting impact on the structural reliability of solar cells

100%

Kilikevičienė K. , Matijošius J. , Fursenko A. , Kilikevičius A.

tom Vol. 21, no. 2

275--281

The mandatory tests of resistance to hail is carried out in order to qualify solar cell modules according to standards (IEC 61215 and IEC 61646). The efficiency of modern photovoltaic systems decreases significantly, when the crystalline structure of solar cells is damaged as a result of climatic factors, such as wind, hail, etc., which are similar to mechanical-dynamic effects. This work presents a conducted research of efficiency and reliability of solar cells, simulating hail effects. A testbed was created specifically for carrying out experimental research. During the research, solar elements were exposed to impact, cyclic dynamic loads, with the frequency of revolutions of the balls simulating hail ranging from 5 to 20 Hz, the amplitude of the impact excitation acceleration of the solar cell - up to 986 m / s2 and the force amplitude - up to 1129 N. Experimental research results revealed the reliability of photovoltaic modules of different sizes during the simulation of hail. The proposed assessment methodology of hail effects can be successfully applied in studies of the influence of mechanical-dynamic effects of solar cells of different structures.

Przy kwalifikacji modułów ogniw słonecznych do użytkowania przeprowadza się obowiązkowe badania odporności na gradobicie zgodnie z normami IEC 61215 i IEC 61646. Wydajność nowoczesnych systemów fotowoltaicznych znacznie spada, gdy struktura krystaliczna ogniw słonecznych ulega uszkodzeniu w wyniku czynników klimatycznych, takich jak wiatr, gradobicie itp., które przypominają w swoim działaniu obciążenia mechaniczno-dynamiczne. W pracy przedstawiono wyniki badań symulacyjnych wpływu gradobicia na wydajność i niezawodność ogniw słonecznych. Badania prowadzono na specjalnie do tego celu skonstruowanym stanowisku testowym. Podczas badań, elementy słoneczne były wystawiane na cykliczne obciążenia dynamiczne wywoływane uderzeniami kulek symulujących grad o częstotliwości obrotów od 5 do 20 Hz przy amplitudzie przyspieszenia wzbudzenia uderzeniowego ogniwa słonecznego wynoszącej do 986 m/s2 oraz amplitudzie siły do 1129 N. Wyniki symulacji pozwoliły ocenić niezawodność modułów fotowoltaicznych o różnych rozmiarach. Proponowaną metodologię oceny wpływu opadów gradu można z powodzeniem stosować w badaniach oddziaływania obciążeń mechaniczno-dynamicznych na ogniwa słoneczne o różnych strukturach.

Analysis of the construction of the car trailer frame in terms of changing the assembly technology

88%

Caban J. , Nieoczym A. , Matijošius J. , Kilikevičius A. , Drozd K.

Zeszyty Naukowe. Transport / Politechnika Śląska

2024

tom z. 124

47--61

Car trailers are quite a popular means of transport and are offered in many versions, from single axle light trailers with a maximum permissible weight of 750 kg, through two- or more-axle specialized trailers. The issues of research car trailers focus on two directions: testing the driving properties and analysing the strength of the supporting frame system. Issues related to the construction of light trailers are often common to trailers used in agriculture or general transport. In this article, based on a mass-produced car trailer, an analysis was carried out regarding the choice in the technology of making the supporting structure consisting of a lower frame and an upper frame. The term upper frame should be understood as the structure on which the lifted load box rests. The costs of materials, assembly and technological possibilities of small-scale production were taken into account. In addition, strength analyses of the numerical models were carried out for critical areas of the frame during operation. After considering the unit costs for each of the analysed assembly technologies, it was shown that riveting would be the cheapest. However, the most suitable method of assembly is welding, as it allows the use of standard profiles.

Improving Diesel Engine Reliability Using an Optimal Prognostic Model to Predict Diesel Engine Emissions and Performance Using Pure Diesel and Hydrogenated Vegetable Oil

75%

Žvirblis T. , Hunicz J. , Matijošius J. , Rimkus A. , Kilikevičius A. , Gęca M.

2023

tom Vol. 25, no. 4

art. no. 174358

The reliability of internal combustion engines becomes an important aspect when traditional fuels with biofuels. Therefore, the development of prognostic models becomes very important for evaluating and predicting the replacement of traditional fuels with biofuels in internal combustion engines. The models have been made to model AVL 5402 engine emission, vibration, and sound pressure parameters using a three-stage statistical regression models. The fifteen parameters might be accurately predicted by a single statistic presented here. Both fuel type (diesel fuel and HVO) and engine parameters that can be adjusted were considered, since this analysis followed the symmetry of the methods. The data analysis process included three distinct steps and symmetric statistical regression testing was performed. The algorithm examined the effectiveness of various engine settings. Finally, the optimal fixed engine parameter and the optimal statistic were used to construct an ANCOVA model. The ANCOVA model improved the accuracy of prediction for all fifteen missing parameters.