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Tytuł:
Aluminium foam testing for impact energy absorption aims
Autorzy:
Niezgoda, T.
Miedzińska, D.
Powiązania:
https://bibliotekanauki.pl/articles/245628.pdf
Data publikacji:
2009
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
aluminium foam
microstructure modelling
open cell foam
closed cell foam
Opis:
Aluminium foams are a new group of materials used for impact energy absorbing elements. They are light (typically 10-25% of the density of the metal they are made of) and stiff, and are frequently proposed as a light weight structural material. That is why they often are applied in automotive and transport industry solutions, for example as parts of bumpers. The methods of numerical modelling for open and closed cell aluminium foams are presented in the paper as well as closed and open cellfoam microstructure model. The numerical models of foam ideal microstructures created with shell finite elements are shown. The models were developed on the basis of Kefain tetrakaidecahedrons - structures consisting of six squares and eight hexagons. In the case of closed cell foams, the polyhedron with full walls was adopted. In the case of open cell foams the circle wholes were removed from polyhedron surfaces. Then the numerical analysis of a created models compressive test was carried out with the usage of LS Dyna computer code. The nonlinear procedures were applied. The results were analyzed in the scope of energy absorbing properties of aluminium foams.
Źródło:
Journal of KONES; 2009, 16, 3; 283-289
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of coal structure in the aspect of gas content
Autorzy:
Niezgoda, T.
Miedzińska, D.
Małek, E.
Powiązania:
https://bibliotekanauki.pl/articles/298731.pdf
Data publikacji:
2013
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
carbon dioxide
methane
porosity of coal
Opis:
The problem of methane existence in coal beds has been known for many years. It was and still is a danger to coalminers. The aim of the research presented in the paper is to show and assess the porosity structure (especially micro and nanoporosity) in accordance to the dimensions of carbon dioxide particle. The characteristic surface morphology of the sample and the disclosure of carbon porous structure was obtain using the scanning electron microscope (SEM). The presented study of the coal microstructure is a part of the coal demethanation method with the use of liquid CO2, that was proposed by Military University of Technology. Based on the results of laboratory tests may be noted that the analyzed coal has a granular structure. It is also visible that that the structure is stratified, and there is a lot of cracks and free space between grains, which can accumulated methane in coal structure. The nanoporosity of the coal grains was observed during SEM study. The sizes and shapes of pores are miscellaneous. However the dimension of 62-300 nm allow to draw a conclusion, that the nanopores can contain a few particles of CH4 (4 A), which can be released by the CO2 particle (2.54 A). Finally, on the base of presented research it can be concluded that the method of coal demethanation with the use of CO2 can be economically and ecologically effective, and can increase the miners safety.
Źródło:
AGH Drilling, Oil, Gas; 2013, 30, 1; 169-179
2299-4157
2300-7052
Pojawia się w:
AGH Drilling, Oil, Gas
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of influence of temperature on wellbore tubing dimensions
Autorzy:
Kwietniewski, M.
Miedzińska, D.
Niezgoda, T.
Małek, E.
Powiązania:
https://bibliotekanauki.pl/articles/241587.pdf
Data publikacji:
2016
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
wellbore
tubing
heat
thermal extension
pipe
steel P110
thermal analyses
finite element method
Opis:
The construction of exploitation wellbore is complex, it consists of several columns of pipelines which perform different tasks. It is very important to preclude flow of reservoir fluid between wellbore and ground. Tubing is a kind of a pipeline which is very important element of oil and gas wellbore construction. It allows to transport fracturing medium between wellbore station and underground deposit. Manufacture quality and correct mounting of tubing in the wellbore are the key for effective exploitation. However, during work those pipes are subjected to changeable loads which results in temperature value changes for example. That temperature variations can be caused by cold medium transport inside the pipe. In the paper, analyses of influence of temperature value changes on the tubing shrinkage were presented. Numerical analyses of section of pipe vertically located in the wellbore and loaded with changeable temperature were carried out. The calculations were made with the use of coupled structural and thermal analyses. Received results of tubing shrinkage for fragment of pipe were adapted to the column of pipes of 3000 m length. Results of numerical analyses were verified with the analytical calculations. Material of tubing was assumed as steel P110 which is often applied in the wellbore construction.
Źródło:
Journal of KONES; 2016, 23, 4; 269-273
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of 3D printing technology for mechanical properties study of the photopolymer resin used to print porous structures
Autorzy:
Małek, Ewelina
Miedzińska, Danuta
Popławski, Arkadiusz
Szymczyk, Wiesław
Powiązania:
https://bibliotekanauki.pl/articles/950080.pdf
Data publikacji:
2019
Wydawca:
Uniwersytet Warmińsko-Mazurski w Olsztynie
Tematy:
mechanical properties
rapid prototyping
SLA
stereolitography
fractal models
Opis:
In the field of numerical research there are various approaches and methods for structures of porous materials modeling. The solution is the use of fractal models to develop the porous structure. In the case of modeling the geometry of natural (random) materials, there is a problem of compatibility of the FE model geometry and real one. This is a source of differences between the results of calculations and experimental ones. Application of 3D printing technology will allow to receive a real structure in a controlled manner, which exactly reflects the designed structure and is consistent with the geometry of the numerical model. An experimental research on the standard samples made of photopolymer resin using 3D printing technique was presented in the paper. The aim of the research was to determine the base material properties and, consequently, to select the constitutive model, which is necessary to carry out numerical analyses.
Źródło:
Technical Sciences / University of Warmia and Mazury in Olsztyn; 2019, 22(2); 183-194
1505-4675
2083-4527
Pojawia się w:
Technical Sciences / University of Warmia and Mazury in Olsztyn
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Badania eksperymentalne wpływu dwutlenku węgla na strukturę porowatą i właściwości mechaniczne skały łupkowej
Experimental study on influence of carbon dioxide on porous structure and mechanical properties of shale rock
Autorzy:
Miedzińska, D.
Powiązania:
https://bibliotekanauki.pl/articles/210249.pdf
Data publikacji:
2017
Wydawca:
Wojskowa Akademia Techniczna im. Jarosława Dąbrowskiego
Tematy:
geomechanika
skały łupkowe
dwutlenek węgla
geomechanics
shale rock
carbon dioxide
Opis:
Skały łupkowe są formacjami geologicznymi, może w nich występować materia organiczna, dzięki której mogą powstać niekonwencjonalne złoża gazu. Podczas ich interakcji z dwutlenkiem węgla, który może być stosowany jako czynnik szczelinujący do wydobycia gazu, zachodzi wiele zjawisk mających wpływ na strukturę i parametry wytrzymałościowe skały. W pracy przedstawiono badania zmian struktury skały łupkowej pod wpływem oddziaływania dwutlenku węgla w stanie nadkrytycznym oraz ich wpływ na właściwości wytrzymałościowe skały. Badania strukturalne zostały przeprowadzone przy użyciu technik mikroskopowych przy różnych powiększeniach obrazu. Jako test właściwości wytrzymałościowych przyjęto próbę jednoosiowego ściskania. W wyniku prac zaobserwowano pewną zależność. Im bardziej zmniejszyła się porowatość badanej próbki po infiltracji dwutlenkiem węgla w małych powiększeniach, tym bardziej zwiększyła się jej porowatość w dużych powiększeniach i tym mniejszą osiągnęła wytrzymałość na jednoosiowe ściskanie.
Shale rocks are geological formations which can be unconventional gas reservoirs. During their interaction with carbon dioxide, which can be used as a fracturing fluid in shale gas recovery process, many phenomena take place that can influence rock structure and mechanical properties. The research on changes in rock structure under super critical carbon dioxide interaction and their influence of shale properties were presented in the paper. The structural tests were carried out with the use of microscopic techniques with different resolutions of visualization. The uniaxial compression test was applied as a mechanical properties’ assessment experiment. As a result of research, some dependence was observed. The bigger decrease was in porosity after infiltration in lower zooms, the bigger increase in porosity in high zooms and mechanical properties was noticed.
Źródło:
Biuletyn Wojskowej Akademii Technicznej; 2017, 66, 4; 167-178
1234-5865
Pojawia się w:
Biuletyn Wojskowej Akademii Technicznej
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Blast loading on aluminum foam microstructure
Autorzy:
Miedzińska, D.
Panowicz, R.
Powiązania:
https://bibliotekanauki.pl/articles/244041.pdf
Data publikacji:
2010
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
microstructure
aluminium foam
strain rate effect
Opis:
One of the possible options as a material for protective layers is aluminum foams which become also very popular due to their lightweight and excellent plastic energy absorbing properties. Such characteristics have been appreciated by the automotive industry with continued research to further understand foam properties. Compressed foaming materials exhibit extensive plastic response, while the initial elastic region is limited in tension by a tensile brittle-failure stress. Aluminum foams have become also an attractive material as blast protective layers due to their desirable compressive properties. With different material engineering techniques (as, for example double-layer foam cladding) they can be customized to achieve the most desirable properties. Energy absorption capacity of foams microstructures under blast load was analytically confirmed based on a rigid-perfectly plastic-locking foam model Initial research indicates that energy absorbed by the cladding is much larger than that under quasi-static conditions due to strain rate effect. In this paper a numerical model of a closed cell aluminum foam idealistic microstructure was presented. The quasi static compression tests were carried out with the use of LS Dyna computer code. Then the sample was numerically loaded with the blast wavefrom detonation of explosives and its behavior was analyzed. The results ofboth analyses were compared.
Źródło:
Journal of KONES; 2010, 17, 3; 287-292
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Carbon dioxide geosequestration method coupled with shale gas recovery
Autorzy:
Niezgoda, T.
Małek, E.
Miedzińska, D.
Powiązania:
https://bibliotekanauki.pl/articles/298651.pdf
Data publikacji:
2013
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
shale gas
carbon dioxide
geosequestration
Opis:
Shale gas in the United States over the past decade, and interest has spread to potential gas shales in Canada, Europe, Asia, and Australia. One analyst expects shale gas to supply as much as half the natural gas production in North America by 2020. Carbon dioxide capture and storage (CCS) is a set of technologies for the capture of CO2 from its anthropogenic point sources, its transport to a storage location, and its geosequestration. This is only one, though very important, option in a portfolio of actions to fight the increase of atmospheric CO2 concentration and to mitigate climate change, while at the same time allowing for the continued use of fossil fuels. Deployment of CCS technologies is expected to be limited in the next 5-10 years, but to contribute significantly to the reduction of CO2 emissions 20 years from now. Capture of CO2 using existing separation techniques can be applied to large point sources, i.e. power plants or industrial plants; CO2 can be easily transported over large distances using pipelines and ships; finally CO2 can be permanently stored in suitable deep geological formations, namely deep saline aquifers, oil or gas reservoirs, and unmineable coal seams, or it can be fixed in carbonates. The paper deals with the innovative method of carbon dioxide storage coupled with gas shale fracturing and methane recovery developed in the Military University of Technology. It allows to effectively mine the shale gas and to store carbon dioxide in shale rock. It must be noticed that CO2 pollution is a very important problem in Poland, because of European Union CO2 limits. Also carbon dioxide thermodynamic process of decompression numerical calculation, which simulates the injection of the cold liquid gas into the shale formation (high temperature and pressure conditions) and its influence on shale rock fracturing as well as initial experimental verification of the method was presented in the paper.
Źródło:
AGH Drilling, Oil, Gas; 2013, 30, 1; 161-167
2299-4157
2300-7052
Pojawia się w:
AGH Drilling, Oil, Gas
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
CO2 - CH4 sorption induced swelling of gas shales: An experimental study on the Silurian shales from the Baltic Basin, Poland
Autorzy:
Miedzińska, D.
Lutyński, M.
Powiązania:
https://bibliotekanauki.pl/articles/109897.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
shale rock
swelling
methane
carbon dioxide
sorption
Opis:
The main aim of the research presented in the paper was to study the phenomena of shale swelling induced by CH4 and CO2 sorption. In the study, a Silurian gas shale sample from the Baltic Basin in Poland was used. Samples represented typical characteristic features of polish shale gas formations with relatively low total organic carbon (0.8%) and high clay mineral content. The first part of the study was devoted to competitive adsorption of CO2 and CH4. The second part was devoted to observation of the sorption induced swelling phenomena, where sample linear strains were monitored with the use of strain gauges. Swelling tests were conducted up to the pressure of approximately 8 MPa with CO2, CH4 and helium as the baseline. Experimental results were compared with the Seidle and Huitt model where Langmuir constants where determined with volumetric sorption tests. Results of the study showed that matrix swelling in case of CO2 adsorption was greater than in the case of CH4 adsorption. The swelling value was directly proportional to adsorption and was about 5 to 10 times smaller than in the case of coal. Sorption of methane and carbon dioxide in the gas-bearing shale was about 10-times lower than in hard coals. The Seidle and Huitt model developed for coals was equally suitable to describe the processes of shale swelling.
Źródło:
Physicochemical Problems of Mineral Processing; 2018, 54, 2; 415-427
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Comparative study of hybrid foam microstructure models
Autorzy:
Szymczyk, W.
Miedzińska, D.
Powiązania:
https://bibliotekanauki.pl/articles/246261.pdf
Data publikacji:
2010
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
FEM modelling
foam structure
elastomer filament
geometry orientation
Opis:
Cellular solids are materials made out of solid strut or thin plate like structures bridged together. They occur in nature in the form of honeycombs, wood, bone, cork etc. These materials possess a unique combination of properties such as low thermal conductivitv, low density and high energy-absorption. Foams are a class of cellular solids, generally made by dispersing gas into a liquid material and then cooling it to solidify. They are categorized as open-cell and closed-cell foams. Depending on the solid materials that are made into foams, they are also categorized as polymeric foams, metallic foams, and ceramic foams. Due to developments in material science and manufacturing lechniques, advanced foams have found potential for use in automobile, aircraft, and space vehicle structures. In the paper the comparative study of the hybrid foam microstructures is presented. Hybrid foam is a new, still developed material that is built of the aluminum open cell foam matrix filled with other material (here: elastomer). The numerical models based on cubic geometry in different configurations are developed. The FE analysis of the compression test is curried out. The results are presented and analyzed due to the microstructure geometry influence on the material behaviour.
Źródło:
Journal of KONES; 2010, 17, 4; 505-511
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Energia z głębokich pokładów gorących suchych skał (HDR) do poprawy bezpieczeństwa infrastruktury krytycznej Polski
Autorzy:
Niezgoda, T.
Miedzińska, D.
Sławiński, G.
Powiązania:
https://bibliotekanauki.pl/articles/111049.pdf
Data publikacji:
2018
Wydawca:
Centrum Rzeczoznawstwa Budowlanego Sp. z o.o.
Tematy:
bezpieczeństwo energetyczne
energia
wydobycie ciepła
skały
infrastruktura krytyczna
energy security
energy
heat extraction
rocks
critical infrastructure
Opis:
W artykule przedstawiono zarys technologii wydobycia ciepła z głębokich pokładów gorących suchych skał (HDR – hot dry rocks), możliwości jej implementacji na terenie Polski oraz jej zalety w aspekcie zastosowania do poprawy bezpieczeństwa infrastruktury krytycznej, jak również poprawy bezpieczeństwa energetycznego Polski.
In the paper the scheme of technology of heat recovery from deep beds of hot dry rocks (HDR) and the possibilities of its applications in Poland were presented. Also the advantages of the HDR technology implementation in accordance to critical infrastructure safety improvement as well as for Poland energetic safety increase were shown.
Źródło:
Inżynieria Bezpieczeństwa Obiektów Antropogenicznych; 2018, 3-4; 65-69
2450-1859
2450-8721
Pojawia się w:
Inżynieria Bezpieczeństwa Obiektów Antropogenicznych
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Experimental and analytical research on resonance phenomena of vibrating head with MRE regulating element
Autorzy:
Miedzińska, D.
Gieleta, R.
Osiński, J.
Powiązania:
https://bibliotekanauki.pl/articles/265035.pdf
Data publikacji:
2015
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
vibratory pile hammer
resonance
vibrations
Fourier analysis
analiza Fouriera
wibracje
rezonans
Opis:
A vibratory pile hammer (VPH) is a mechanical device used to drive steel piles as well as tube piles into soil to provide foundation support for buildings or other structures. In order to increase the stability and the efficiency of the VPH work in the over-resonance frequency, a new VPH construction was developed at the Military University of Technology. The new VPH contains a system of counter-rotating eccentric weights, powered by hydraulic motors, and designed in such a way that horizontal vibrations cancel out, while vertical vibrations are transmitted into the pile. This system is suspended in the static parts by the adaptive variable stiffness pillows based on a smart material, magnetorheological elastomer (MRE), whose rheological and mechanical properties can be reversibly and rapidly controlled by an external magnetic field. The work presented in the paper is a part of the modified VPH construction design process. It concerns the experimental research on the vibrations during the piling process and the analytical analyses of the gained signal. The results will be applied in the VPH control system.
Źródło:
International Journal of Applied Mechanics and Engineering; 2015, 20, 1; 201-208
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Experimental research on influence of gas impact on thermal and mechanical properties of auxetic material covered with titanium silicide coating
Autorzy:
Miedzińska, D.
Gieleta, R.
Małek, E.
Zasada, D.
Stankiewicz, M.
Marszałek, K.
Powiązania:
https://bibliotekanauki.pl/articles/201182.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Ti-Si layers
damage
impact
thermal resistance
SEM
auxetic materials
Ti-Si
uszkodzenia
uderzenia
opór cieplny
materiały auksetyczne
Opis:
The aim of the presented work was to study the auxetic textiles covered with titanium silicide coating. The research was carried out to develop the material structure, which will be used for protective clothing, e.g. for firemen. The new material should be characterized by increased heat resistance coupled with protection against gas pressure impact caused e.g. by gas installation damage. In the paper, an assessment of the change in heat resistance properties of a Ti-Si coated auxetic textile loaded with gas pressure impulse was carried out.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2018, 66, 2; 165-172
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Failure analysis of chosen 3D numerical models of an open cell foam
Autorzy:
Szymczyk, W.
Miedzińska, D.
Powiązania:
https://bibliotekanauki.pl/articles/243845.pdf
Data publikacji:
2010
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
FEM modelling
open cell foam structure
Opis:
Metal and polyurethane foams exhibit interesting properties. They are light, have good acoustic and/or magnetic isolation as well as ability to absorb the vibration and impact energy. They are used for sandwich panels, impact absorbers (i.e. as elements of the buffer constructions in rail vehicles), fillers ofconstruction parts, bodies of vehicles (i.e. floating combat vehicles) and for dividing walls of vessels and others. Speciflcally made open cell foams demonstrate auxetic properties and the shape memory effect. Such materials are very good for seats in aircrafts which may protect pilots and passengers during crashes and limit heavy backbone injuries. Foams are used for filtering purposes. Foams or their in combination with different types of fillers (i.e. elastomers) or the ceramic reinforcement may be used in impact energy absorbing panels for military aim (protection against an explosion shock wave and splinters). In the paper aluminium open-cell foam structures were investigated for their energy absorption ability. For this purpose a series of numerical 3D models were applied. Geometry of the models was based on Kehin's polyhedrons. Tests of uniaxial compression were simulated with the use of LS-Dyna computer code. Complex contact phenomena were considered. Preliminary test were performed with the use of single foam cell models. Further simulations were conducted using 3x3x3 cell models. The results were analyzed as force/time characteristics.
Źródło:
Journal of KONES; 2010, 17, 1; 449-454
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
FEM analysis of proppant sticking in rock cracks
Analiza MES wciskania proppantu w pęknięcie skalne
Autorzy:
Kwietniewski, M.
Miedzińska, D.
Niezgoda, T.
Powiązania:
https://bibliotekanauki.pl/articles/231026.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
analiza MES
proppant
skała łupkowa
pęknięcie
szczelinowanie
kontakt
Newmark
FEM analysis
shale rock
crack
fracturing
contact
Opis:
The problem of effective gas extraction from Polish shale rocks is an interesting research subject for scientists. A properly selected proppant, which protects cracks from closing during the fracturing process, inestimably contributes to an increase of extraction. Grains of proppant are transported along with a fracturing medium to reach the deepest regions of the crack. The proper support of the crack provides an easy flow of gas, therefore it is important in terms of extraction efficiency. This paper shows the interactions of a proppant grain with the crack surface in shale rock. FEM analysis was conducted to observe the stress region, which is generated as a result of pressing the grain into the crack surface. A model of a sphere which was pressed into the rock model with constant velocity was applied. The received results of stress depend on material properties and a range of proppant grain pressing.
Terytorium Polski od kilku lat jest obiektem wzmożonych badań mających na celu opracowanie opłacalnej technologii wydobycia gazu z łupków. Polskie skały łupkowe różnią się pod względem fizycznym i chemicznym od tych występujących w Ameryce Północnej, są rozlokowane również na innej głębokości. Inna budowa skały stawia zatem nowe wyzwania dla wiertnictwa otworowego. Procesy szczelinowania zachodzą w nieco inny sposób, zatem konieczne jest opracowanie nowej technologii wydobycia. Jednym z ważniejszych aspektów tych badań jest dokładna analiza zachowania się skały obciążonej ciśnieniem szczelinowania. Do rozważenia jest tu mechanizm powstawania i propagacji pęknięcia oraz optymalny sposób podparcia szczeliny po zabiegu szczelinowania. Tę funkcję mają pełnić proppanty, które dostają się do złoża wraz z czynnikiem szczelinującym. Ziarenka, najczęściej ceramiczne o dużej twardości mają za zadanie zaklinować się w skale, aby utworzyć maksymalne rozwarcie szczeliny. Oczywiście, przy ogromnych naprężeniach wewnętrznych górotworu nastepuje wgniatanie ziaren w powierzchnię skały, co powoduje zmniejszenie przekroju poprzecznego szczeliny, a w skrajnych przypadkach może prowadzić do całkowitego zamknięcia szczeliny. Do analizy MES opracowano model geometryczny. Przyjęto, że model skały to czwarta część walca ze szczeliną w środkowej częćci o promieniu 1 mm. Wygenerowano model skały łupkowej o promieniu 8 mm oraz długości 10 mm. Analogicznie do modelu skały, przyjęto ziarenko proppantu jako 1/4 kuli. Dyskretyzację modelu przeprowadzono w oprogramowaniu LS – PrePost za pomocą elementów ośmiowęzłowych. Utworzony model składa się z 29554 elementów oraz 60696 węzłów.
Źródło:
Archives of Civil Engineering; 2018, 64, 2; 55-65
1230-2945
Pojawia się w:
Archives of Civil Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of the volume fraction of the carbonyl iron particles on the mechanical properties of the magnetorheological elastomers
Autorzy:
Sławiński, G.
Niezgoda, T.
Miedzińska, D.
Gieleta, R.
Powiązania:
https://bibliotekanauki.pl/articles/247437.pdf
Data publikacji:
2010
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
smart materials
magnetorheological elastomer (MRE)
finite element method (FEM)
Opis:
Magnetorheological materials belong to the group of the so called intelligent materials. Their rheological properties can be changed in a large range using an external magnetic field. That is why they fmd ever growing application in modern technical equipment, among others in controlled dampers, clutches, sensors etc. In the paper, a numerical strength analysis of a magnetorheological material was presented. The influence of the volume fraction of carbonyl iron particles (the share of the carbonyl iron particles varied from 1.5 to 33.0 vol. %.) on the mechanical properties of the material were investigated, in particular on the Young's modulus variation. Experimental tests were carried out for specimens made of pure PU 70/30 elastomer with iron particles. They induded uniaxial compression tests. In the farmer case, specimens were in a shape of a cylinder with a diameter of 20 mm and a height of 25-30 mm. The results of experimental tests carried out in order to determine the parameters necessary to build the numerical model were induded in the paper. In the paper, an algorithm developed for determining the parameters for modelling the structure was presented. A fragment of the structure, containing several particles of iron and some quantity of elastomer, corresponding to the assumed volume fractions, was subjected to numerical analysis.
Źródło:
Journal of KONES; 2010, 17, 3; 401-406
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 34

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