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Mining - Informatics, Automation and Electrical Engineering
No full textIn recent years, there has been greater interest in rapid prototyping methods employed in various industries. Prototypes are increasingly often made using 3D printing technology, which is mainly due to the relatively low costs of developing and producing such a structure and the short time needed for their physical production. The work presents the possibility of using rapid prototyping techniques, such as water propulsion nozzles. They are mainly used in the energy industry, e.g. for the production of water mist in jets or condensers. Such nozzles enable the formation of a stream, and its range and efficiency depend on the design requirements. CFD (computational fluid dynamics) tools and 3D printing will be used to assess the nozzle’s effectiveness. A 3D printer based on FDM technology was used to produce nozzle prototypes. The CFD results were verified with experiment. Analyzes for four different nozzle shapes are presented and the discrepancies between the results of the initial experimental and numerical analyses are explained. To indicate the imperfections resulting from 3D printing, a 3D scanner was used to show the internal cross-section of the nozzle. The research conducted indicates the significant potential of 3D printing in rapid prototyping and its effectiveness in creating functional models for various engineering applications.Krakówwersja wydawnicz
Advanced Electronic Materials
No full textWith the advancement in smart electronic devices and self-powered devices, the demand for piezoelectric polymers found potential research interest. Among these, electrospun polyvinylidene fluoride (PVDF) fibers have gained attention for energy harvesting due to their flexibility and higher piezoelectric coefficient. We compare various methods to enhance PVDF's piezoelectric properties, including different solvents (DMAc, DMF), conductive filler (rGO), and annealing as post-treatment. Our results indicate that PVDF/rGO fibers in DMAc solvent exhibit the highest β phase fraction and crystallinity. Moreover, for the first time, we present the piezoelectric properties of PVDF/rGO electrospun single fiber using high voltage switching spectroscopy piezoelectric force microscopy (HVSS-PFM). The highest piezoelectric coefficient (d33) was measured for PVDF/DMAc-rGO composite fibers. Notably, PVDF/rGO in DMAc solvent significantly improves the piezoelectric coefficient, leading to a remarkable fourfold increase in power density compared to pure PVDF, making it a promising material for energy harvesting applications.wersja wydawnicz
Mining - Informatics, Automation and Electrical Engineering
No full textW artykule zaprezentowano projekt, który stanowi dowód na przydatność organizacji studenckich oraz skuteczność popularyzacji zaawansowanych technologii i rozwiązań w przemysłowej przyszłości. Opracowany przez studentów autonomiczny łazik planetarny, wykorzystując filtr Kalmana oraz pozostałe algorytmy odpowiedzialne między innymi za dynamiczne mapowanie terenu oraz wyznaczanie ścieżek, jest w stanie bezkolizyjne poruszać się nawet w najbardziej wymagających środowiskach. Łazik wykorzystuje również skonstruowane przez studentów ramię 6DOF do swobodnego podejmowania zadań manualnych, takich jak pobieranie próbek gleby czy zadania naprawcze. Jest on także wyposażony w wiertło, które umożliwi pobranie próbki gleby z głębokości co najmniej 30 cm, co mocno wesprze badania historii geologicznej regionu. Robot został wielokrotnie przetestowany z sukcesem na zawodach łazików planetarnych, co potwierdza potencjał takich platform w eksploracji kosmicznej i możliwości zastosowania w przemyśle, szczególnie w trudno dostępnych obszarach górniczych. Prezentowany projekt stanowi inspirację dla przyszłych młodych inżynierów i naukowców, otwierając perspektywy na wykorzystanie podobnych technologii w efektywniejszym i bezpieczniejszym funkcjonowaniu przemysłu.Krakówwersja wydawnicz
Mining - Informatics, Automation and Electrical Engineering
No full textW artykule przedstawiono wyniki badań laboratoryjnych zmęczenia próbek wykonanych z pełnowymiarowych żerdzi pompowych ze stali 15H2GMF w różnych środowiskach korozyjnych. Dla porównania podobne badania przeprowadzono dla zmęczenia korozyjnego próbek wykonanych z pełnowymiarowych żerdzi ze stali 20N2M, 15H2NMF i 15N3MA. Granica wytrzymałości badanych prętów ze stali 15H2GMF w solance złożowej jest o 22 niższa niż stali 20N2M i o 13 niższa niż stali 15H2NMF, a w środowisku symulującym działanie H2S jest o 34 niższa niż dla stali 20N2M i o 32 niższa od stali 15H2NMF. Przedstawione wyniki uzyskano przy zastosowaniu złożonej metody powierzchniowego wzmacniania żerdzi, która została opracowana w laboratorium Katedry Maszyn i Urządzeń Naftowych i Gazowych Narodowego Uniwersytetu Technicznego Nafty i Gazu w Iwano-Frankiwsku i przetestowana w NGVU Dolynanaftogaz.Krakówwersja wydawnicz
Journal of Geotechnology and Energy
No full textThis paper addresses the historical environmental impact of Bydgoszcz’s ‘Old Gasworks,’ located on Jagiellońska Street on the Brda River—one of Poland’s oldest and longest-operating gas production facilities. Municipal gas derived from dry coal distillation served both municipal and industrial purposes until 1973. However, the production process, marked by significant nuisances, particularly affected the ground and water environment. Pollutants, primarily organic compounds such as aromatic hydrocarbons, including PAHs (polycyclic aromatic hydrocarbons), and BTEX hydrocarbons (benzene, toluene, ethylbenzene, xylenes), phenol and mineral oil, entered the environment through equipment failures, leaks, and the improper storage of wastewater and technological waste. One of the major sources of contamination was inadequately executed construction activities related to the dismantling of installations and the liquidation of sewage and waste storage tanks. This paper presents the findings of a comprehensive study focusing on hydrocarbon concentrations in groundwater at the ‘Old Gasworks’ in Bydgoszcz and proposes effective methods for treating the water environment.Krakówwersja wydawnicz
Nauka – Technika – Technologia : seria wydawnicza AGH. Tom 8
No full textÓsmy tom monografii z multidyscyplinarnej serii "Nauka - Technika - Technologia" publikowanej w formule open access. Książka zawiera artykuły dotyczące różnorodnych kierunków badawczych AGH, obejmujące zarówno tradycyjne obszary, takie jak górnictwo i hutnictwo, jak i bardzo nowoczesne obszary IT oraz wszelkie inne specjalności i kierunki prowadzone na Uczelni.131 s.Krakówpublikacja wielotematycznawersja wydawnicz
Contemporary challenges in management and economy in the area of COVID-19
No full textThe changes caused by a pandemic have a very strong impact on many areas of activity. The long-term plans set out in the operating strategy of companies and organizations have become of little use in the new business conditions. Many companies are urgently required to develop a new strategic approach that takes account of the post-pandemic situation. The question is whether the traditional approach to strategy building and strategic management can be applied. The article analyzes strategic management in new conditions and proposes a new agile approach called digital stractics.Krakówrozdziałwersja wydawnicz
Smart Materials and Structures
No full textMagnetorheological (MR) fluids are suspensions of fine, low-coercivity, high magnetizable particles in a continuous liquid phase. When subjected to magnetic field, the material exhibits a rapid change in the apparent viscosity of several orders of magnitude. This unique capability has been successfully exploited in automotive semi-active suspensions systems or systems for manufacturing high quality optics. In a majority of the existing systems, the rheology of MR fluids is controlled by an external uniform field oriented perpendicularly to the fluid flow direction. In general, it is an inherent feature of MR systems operating in flow, shear or squeeze modes, respectively. There is an experimental evidence that the behavior of MR fluids in the so-called pinch-mode (in which the fluid is subjected to non-uniform magnetic field distributions ) clearly stands out against the remaining three operating modes. With the predecessors, the flow through the channel occurs once a pressure across it exceeds the field-dependent threshold pressure. For comparison, in pinch mode valves the magnetic flux energizes mostly the layers of the materials near the channel walls. The outcome is a change in the channel’s effective diameter achieved solely via material means without changing its geometry. To study the fluid’s unique behavior in the pinch mode, the authors designed a prototype valve assembly and examined several fluid formulations of various particle concentration levels across a wide range of external (velocity, magnetic field density) stimuli in an organized effort to further comprehend the phenomenon. The obtained data indicate that the magnitude of the particular effect does not only depend on the magnitudes of the magnetic stimuli but also on the particle concentration; the smaller the concentration of particles the more pronounced the pitch mode like behavior is. In general, the authors believe that the study may provide guidelines as to the selection of fluid formulations for developing novel valveless actuators utilizing MR fluids operating in pinch mode.preprin
