Wyniki wyszukiwania - BazTech

1

Management of the manufacturing process and exploitation of steel and composite shipping containers. Case study and life cycle assessment analysis

Wojnowski Jacek

Zeszyty Naukowe Politechniki Morskiej w Szczecinie

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2024

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nr 77 (149)

47--62

EN

This paper takes the form of a comparative life cycle assessment (LCA) analysis of 40-foot steel and composite containers based on GaBi® software. Reducing greenhouse gas emissions can be undertaken, among other things, by reducing the weight of the container, which is possible if lighter materials with comparable mechanical properties to steel are used. The LCA analysis allowed us to estimate the energy consumed and the amount of greenhouse gases emitted during the production of a steel and composite container. It turned out that the energy consumed in the production of the composite and steel container is practically equal in value, provided that carbon fiber from the polyolefin precursor is used in production. The processes with the highest energy intensity for container production are carbon fiber and COR-TEN A® steel production and processing. Changing the container material from steel to composite would save fuel and greenhouse gas (GHG) emissions into the atmosphere by 5.1 % and 18.3 % for road transportation and sea shipping, respectively.

2

Flap strut fairing system expluatation and critical path method use

Zetliņa Sintija, Kleinhofs Martins

Transactions on Aerospace Research

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2024

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Nr 1 (274)

29--44

EN

The flap strut fairing system is made of movable construction inside, but the outer skin is made of composite material. Each day, we can face an expensive repair for movable construction and outer skin as most of the aviation companies are dealing with mechanical issues that are not solved during a long period of time or somebody misses it due to human errors. In this abstract, we will look for options for easier and faster solutions to avoid the expensive operation process.

3

Dodatki mineralne stosowane w betonach kruszywowych o matrycy cementowej

Rubin Jan Antoni

Magazyn Autostrady

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2024

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Nr 5

44--48

PL

W artykule omówiono różnorodne rodzaje dodatków mineralnych, takie jak: pyły krzemionkowe, popiół lotny krzemionkowy czy metakaolin, używane w technologii betonów. Dodatki te pełnią kluczową rolę w procesie hydratacji i twardnienia cementu, poprawiając jego właściwości mechaniczne oraz odporność na warunki środowiskowe. Zaprezentowano również wyniki badań laboratoryjnych określających wpływ dodatków mineralnych na cechy techniczne betonów, takie jak wytrzymałość na ściskanie czy nasiąkliwość, w zależności od rodzaju zastosowanych dodatków oraz temperatury "suszenia”.

EN

The article discusses various types of mineral additives, such as silica fume, silica fl y ash or metakaolin, used in concrete technology. These additives play a key role in the hydration and hardening process of cement, improving its mechanical properties and resistance to environmental conditions. The results of laboratory tests determining the effect of mineral additives on the technical characteristics of concretes, such as compressive strength or water absorption, depending on the type and amount of additives used, are also presented.

4

Solving technological problems of flight services at airport involving composite materials

Romele Marina, Zabirov Anwar, Chatys Rafał, Shestakov Vladimir

Composites Theory and Practice

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2024

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R. 24, nr 2

123--129

EN

Inadequate information support and dispatch of the execution of individual operations of the technological process (especially the repair of composite structures) of aircraft preparation for a flight is one of the reasons for delays. In this regard, there is a need to study the management processes of airport services that ensure the performance of individual technological operations in the preparation of aircraft for departure. This problem belongs to the class of multi-criteria problems, which is solved using simulation modelling. The model is represented by an interconnected set of modules, each of which is associated with a separate technological operation of the general technological process, i.e. the technological process is divided into separate technological operations. The links of individual blocks of the model reflect the information and technological links of a real set of technological operations of flight preparation for departure and are represented by the synthesising algorithm of the simulation model.

5

Experimental study of materials for the filtration of the intake air of the internal combustion engine of a motor vehicle

Dziubak Tadeusz

Combustion Engines

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2024

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R. 63, nr 2

112--125

EN

Fiber composite materials show more favorable filtration properties in terms of filtration efficiency and accuracy, as well as dust absorption. Experimental tests of standard filtration materials based on cellulose, polyester, glass microfiber, cotton and polyester nonwoven fabrics were performed using an original method. Two composite beds consisting of three layers of standard materials were designed using a novel method: K1 (polyester-glass-microfiber-cellulose) and K2 (cellulose-glass-microfiber-cellulose), and determined their effectiveness, the size of dust grains in the cleaned air and the unit dust absorption. It was shown that the K1 composite has high (dpmax = 1.5-3 μm) filtration accuracy, high initial filtration efficiency (99.8%), which shortens the preliminary stage, and extends to 96-98% the duration of the main stage of the filtration process. The K1 composite achieved more than twice the dust mass loading value (kdK1 = 148.9 g/m2), compared to other standard materials. These are parameters that are essential for filter design in automotive technology and can only be obtained through empirical testing. Knowing them will make it possible to make an air filter design with smaller dimensions or to extend vehicle mileage.

6

Tribological properties of piston rings designed for sliding against composite materials in lubricated contacts

Posmyk Andrzej

Tribologia

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2023

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nr 3

53--61

EN

The paper presents basic information on the production, structure and tribological properties of a composite chromium-ceramic coating deposited electrolytically on a cast-iron piston ring for a combustion engine designed for sliding against a composite cylinder liner. The results of comparative tests of two contacts, i.e. cast-iron GJL-250/AlMC and GJL250+Cr-Al2O3/AlMC, are described. The deposition of the Cr- Al2O3 coating on the cast-iron piston ring reduces almost trifold the wear of the piston ring and about 20% the friction resistance in the contact due to the presence of aluminium oxide particles and fibres. The reinforcing phase removed from the chromium layer polishes the chromium and composite sliding surfaces. The places left by the removed particles serve as depots for oil, which reduces the friction forces and minimises oil consumption. The Al2O3 wear debris decreases the roughness of the surfaces in contact, which additionally reduces the friction forces according to the friction hypothesis of Ernst and Merchant.

PL

W artykule opisano podstawy wytwarzania, budowę i właściwości tribologiczne kompozytowej powłoki chromowo-ceramicznej naniesionej elektrolitycznie na żeliwny pierścień tłokowy silnika spalinowego przeznaczony do współpracy z kompozytową tuleją cylindrową. Opisano wyniki badań porównawczych dwóch skojarzeń, tj. żeliwa GJL-250/AlMC i GJL-250+Cr- Al2O3/AlMC. Naniesienie powłoki Cr- Al2O3 na pierścień żeliwny zmniejsza ponad trzykrotnie zużycie pierścienia i około 20% opory tarcia skojarzenia dzięki obecności cząstek i włókien tlenku aluminium. Usunięta z chromu faza zbrojąca działa polerująco na współpracujące powierzchnie chromu i kompozytu. Miejsca po usuniętych cząstkach służą do gromadzenia oleju, co zmniejsza siły tarcia i zużycie oleju. Produkty zużycia Al2O3 zmniejszają chropowatość współpracujących powierzchni, co dodatkowo zmniejsza siły tarcia zgonie z hipotezą tarcia Ernsta i Merchanta.

7

Selection of materials for repairing punctures of metal skin of semi-monocoque structures using composite patches

Godzimirski Jan, Rośkowicz Marek, Barca Iga

Technologia i Automatyzacja Montażu

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2023

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nr 2

19--32

EN

For repairing punctures of skin of semi-monocoque structures under field conditions, simple methods are sought to guarantee the reliability of the repaired structure. Therefore, adhesive joints and composite materials are being increasingly used in repairs. During repairs using adhesion, an important aspect that affects the quality of the joint is the selection of the adhesive and the quality of surface preparation of the parts to be joined. This is necessary to get the right bond strength and durability of the joint in working environments characterized by extreme temperatures and exposure to chemicals and moisture. The purpose of the study was to select an adhesive with good strength properties for bonding AW2024T3 aluminum sheets to carbon and glass composites, and to analyze the effect of metal surface preparation on the strength of adhesive joints (grinding, sandblasting and chemical surface preparation). The tests were carried out on overlap (metal-composite) specimens. For selected adhesives, strength tests were also carried out on specimens replicating the repaired damage with a diameter of 20 mm of metal skin repaired by different methods, including composite patches and adhesive joints. The specimens were loaded in tension and loss of stability. The tests made it possible to determine the requirements for composite patches used for repairing upper and lower airframe wing skins.

PL

Do napraw przebić pokryć konstrukcji półskorupowych w warunkach polowych, poszukuje się prostych metod, które zagwarantują niezawodność naprawianej struktury. Dlatego coraz częściej w naprawach wykorzystuje się połączenia adhezyjne i materiały kompozytowe. Podczas napraw z zastosowaniem klejenia ważnym aspektem, który wpływa na jakość połączenia, jest dobór odpowiedniego kleju oraz jakość przygotowania powierzchni klejonych elementów. Jest to niezbędne do uzyskania odpowiedniej siły wiązania i trwałości połączenia w środowisku pracy, które cechują ekstremalne temperatury oraz narażenie na działanie chemikaliów i wilgoci. Celem badań był dobór kleju o dobrych właściwościach wytrzymałościowych do łączenia blach AW2024T3 z kompozytami węglowymi i szklanymi oraz analiza wpływu przygotowania powierzchni metalowych na wytrzymałość połączeń adhezyjnych (szlifowanie, piaskowanie i chemiczne przygotowanie powierzchni). Badania przeprowadzono na próbkach zakładkowych (metalowo-kompozytowych). Dla wybranych klejów wykonano również badania wytrzymałościowe próbek imitujących naprawione uszkodzenie o średnicy 20 mm pokrycia metalowego naprawianego różnymi metodami, w tym z zastosowaniem łat kompozytowych i połączeń adhezyjnych. Próbki obciążano na rozciąganie i utratę stateczności. Przeprowadzone badania pozwoliły określić wymagania dotyczące łat kompozytowych stosowanych do napraw górnych i dolnych pokryć skrzydeł płatowców.

8

Możliwości wykorzystania gazociągów kompozytowych w rozbudowie gazowej sieci dystrybucyjnej

Kuczyński Szymon, Łaciak Mariusz, Spyra Czesław, Szurlej Adam, Wnęk Przemysław

Przemysł Chemiczny

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2023

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T. 102, nr 6

594--599

PL

Krajowy rynek gazu ziemnego należy do jednego z najszybciej rozwijających się w krajach UE. Światowe doświadczenia w zakresie zastosowania materiałów kompozytowych do budowy sieci gazociągowej oraz wyniki eksperymentalne z testów wykonanych na gazociągu z materiałów kompozytowych wskazują na możliwość zastosowania nowych materiałów w krajowym gazownictwie, zwłaszcza w obszarze dystrybucji gazu. Nowe materiały i nowe technologie wydają się być pomocne dla realizacji planów związanych zarówno z rozbudową gazowych sieci, jak i ich modernizacją.

EN

An exptl. gas pipeline made of a system of fiber-reinforced thermoplastic pipes was tested. Field tests were carried out in the operating facility of Polska Spółka Gazownictwa for 3 months. In real conditions, the continuous flow of natural gas was characterized by variable pressure and flow rate. Measurements of pressure, temp. and gas flow in the exptl. gas pipeline were carried out. The tested composite gas pipeline did not show any damage throughout the test period. There were no signs of material wear on its outer layer. No deformations, cracks, micro-cracks and bulges indicative of material defects were found.

9

Calculation of the strength of reinforced concrete beams strengthened with composite materials

Borysiuk Oleksandr, Trach Roman

Przegląd Naukowy Inżynieria i Kształtowanie Środowiska

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2023

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Vol. 32, No. 1

53--68

EN

Currently, in view of the previous theoretical and experimental researches, the regulatory documents for the calculation of reinforced concrete elements strengthened by composite materials and the calculation and design of fiber reinforced concrete structures are in force in Ukraine and in the world. Simultaneous strengthening of the compressed and tensile zones has not been sufficiently studied. Therefore, further research of reinforced concrete elements, strengthened by modern and highly efficient materials, such as steel fiber concrete and composite materials, is of great theoretical and practical importance. The urgency of the study is due to the obvious need to improve the method of calculation of the reinforced concrete bending elements after simultaneously strengthening compressed and tensile zones.

10

Characterization of defects in composite materials by the intrusive stochastic method using the Gaussian type random variable

Mahmoudi Thinhinane, Oudni Zehor, Berkache Azouaou, Lee Jinyi

Przegląd Elektrotechniczny

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2023

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R. 99, nr 3

246--251

EN

In this work, we propose an approach for the characterization of a composite plate and the evaluation of defects. This approach, called the intrusive stochastic finite element method (ISFEM), consists in considering electrical conductivity as a random variable. The inspection will be done by the non-destructive testing process by eddy currents. The results obtained for two applications are compared with experimental data and those of the Benchmark JSAEM#Problem1.

PL

W tej pracy proponujemy podejście do charakteryzacji płyty kompozytowej i oceny wad. Podejście to, zwane inwazyjną metodą stochastycznych elementów skończonych (ISFEM), polega na uznaniu przewodnictwa elektrycznego za zmienną losową. Inspekcja zostanie przeprowadzona metodą badań nieniszczących prądami wirowymi. Wyniki uzyskane dla dwóch aplikacji są porównywane z danymi eksperymentalnymi i wynikami testu porównawczego JSAEM#Problem1.

11

Zastosowanie wzmocnień kompozytowych w istniejących konstrukcjach

Drobiec Łukasz, Biernacki Jan

Izolacje

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2023

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T. 28, nr 9

48, 50--52

PL

W artykule omówiono praktyczne wykorzystanie materiałów kompozytowych współcześnie stosowanych przy wzmacnianiu istniejących konstrukcji. Zaprezentowano przekrój możliwych zastosowań i objaśniono słuszność i zasady ich doboru. W publikacji można też odnaleźć informacje na temat optymalnych sposobów stosowania wzmocnień zależności od konstrukcji wymagającej wzmocnienia.

EN

The article discusses the practical use of composite materials currently employed in strengthening existing structures. It presents an overview of possible applications and explains the rationale and principles for their selection. The publication also provides information on optimal methods for applying reinforcements, depending on the structure in need of strengthening.

12

Numerical failure analysis of laminated beams using a refined finite element model

Layachi Maroua, Khechai Abdelhak, Ghrieb Abderrahmane, Layachi Safa

Advances in Materials Science

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2023

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Vol. 23, nr 1(75)

32--57

EN

In the present investigation, laminated composite beams subjected to a bending static loading are studied in order to determine their failure mechanisms and the first ply failure (FPF) load. The FPF analysis is performed using a refined rectangular plate element. The present element is formulated based on the classical lamination theory (CLT) to calculate the in-plane stresses. To achieve this goal, several failure criterions, including Tsai-Wu, Tsai-Hill, Hashin, and Maximum Stress criteria, are used to predict failure mechanisms. These criterions are implemented within the finite element code to predict the different failure damages and responses of laminated beams from the initial loading to the final failure. The numerical results obtained using the present element compare favorably with those given by the analytic approaches. It is observed that the numerical results are very close to the analytical results, which demonstrates the accuracy of the present element. Finally, several parameters, such as fiber orientations, stacking sequences, and boundary conditions, are considered to determine and understand their effects on the strength of these laminated beams.

13

Carbon fiber reinforced polymer and tensegrity structures in search of model architectural and engineering solutions

Franta Anna, Zając Dawid

Technical Transactions

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2022

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Vol. 119, iss. 1

art. no. e2022013

EN

The current era of nanomaterials brings advancements in science and technology. This creates new solutions and possibilities in the creation of novel spatial structures. This study leads through the presentation of iconic architectural objects created with the use of high strength composite materials and tensegrity structure. Then presents the design process, numerical simulations of the three-way tensegrity grid prototype module. Static stress simulations were done within the simulation engine of the Fusion 360 software. Moreover, 1:1 scale prototype was developed. It could be used as a modular construction slab of a novel architectural design. One of the key characteristic features of high strength composite materials, high strength-to-weight ratio, combined with tensegrity structures allows to develop lightweight and hence very durable spatial structures. This gives tensegrity structures a very low dead load value as compared to traditional reinforced concrete structures. Thanks to the application of high strength and hence lightweight materials, the dead load of the prototype is only 0,18 kN/m².

14

Turbofan Engines Efficiency, Historical Trends, and Future Prediction: A Review

Kuropatwa Michał, Wegrzyn Nicolas, Kozuba Jarosław

Safety & Defense

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2022

|

2

82--90

EN

Technological development in the aviation business is usually dictated by diverse safety, economic, environmental, and social goals set by governments, regulatory agencies, and the market. Recently, a rapidly increasing interest in making air transportation climate neutral has been observed. The objective of this study is to analyze the historical trends of aircraft engine fuel efficiency, identify parameters affecting engine efficiency and initiate a discussion about future technology development needed to meet the expectations. The commercial turbofan engines test data comparison is provided in this study, followed by a theoretical assessment. The presented test data trends show a clear correlation between specific fuel consumption decrease and engine parameters like bypass ratio and overall pressure ratio increase, which is confirmed by theoretical assessment. Based on performed analysis results, a bypass ratio increase was indicated as the one potential path to reduce aircraft engine fuel consumption. Bypass ratio improvement could be achieved by fan diameter increase and rotation speed reduction in the case of turbofan engine architecture. A larger fan rotor requires a high torque drive and significantly increases engine weight which could be compensated by the lightweight design of the engine components, e.g., by applying composite materials.

15

Application of composite materials in underground mining industry – fore-shaft closing platform

Kamiński Paweł, Niedbalski Zbigniew, Małkowski Piotr, Bozic Darian

Mining Machines

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2022

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vol. 40, iss. 1

19--31

EN

According to Polish law regulations, fore-shaft in underground mines in process of its liquidation must be either filled with bulk material or closed with double-deck platform on its top. As liquidation by closing is cheaper and easier than filling, steel closing platforms are typically used for this purpose. However, steel price fluctuations due to COVID-19 pandemic together with rapid development of composite materials, make application of composite structure a tempting direction. The article presents a design of composite double-deck closing platform for fore-shaft liquidation in one of the collieries located in the eastern area of Silesian Coal Basin. Presented solution was thoroughly calculated and tested and then assembled in the mine. The aim of the research was to prove applicability of composite structures in underground mines with maintaining proper level of safety.

16

Selected issues from the analysis of composite vehicle bodies

Gołębiewski Łukasz, Żach Piotr

Journal of civil engineering and transport

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2022

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Vol. 4, No. 4

9--20

EN

Issues related to designing support frames and bodies for electric delivery vehicles (eVans) are the topic discussed by engineers around the world. Design processes are based on classic solution models which use structural steel profiles. Directions for development include the production of highly tensile steel frames with increased strength parameters. The authors of the article designed and constructed a prototype polymer body for a delivery vehicle. They conducted detailed multi-variant numerical analyses on the prototype and preliminary experimental tests. The obtainedresults clearly confirmed the correctness of the formulated thesis about the possibility of designing bodies made of structural plastics dedicated to electric vehicles. For a static-loaded parts of structure uniform stress distribution without concentration, with maximum stress value of 25 MPa was achived. For parts of structure carrying dynamic loads shape-derived stress concentration is inevitable. Nevertheless, the stress level of 96 MPa is within the limits of strength, due to the velocity-dependent material properties.

PL

Problematyka projektowania ram nośnych i zabudów pojazdów dostawczych elektrycznych typu eVan jest przedmiotem opracowań dyskusji środowiska inżynierskiego na całym świecie. Procesy projektowania bazują na klasycznych modelach rozwiązań wykorzystujących profile ze stali konstrukcyjnej. Kierunki rozwoju obejmują wytwarzanie ram wysoko wytężonych ze stali o podwyższonych parametrach wytrzymałościowych. Autorzy artykułu zaprojektowani i wykonali polimerową prototypową zabudowę pojazdu dostawczego. Przeprowadzili szczegółowe analizy numeryczne na prototypie oraz wstępne badania doświadczalne. Uzyskane wyniki jednoznacznie potwierdziły słuszność sformułowanej tezy o możliwości zaprojektowania zabudów dedykowanychpojazdom elektrycznym z tworzyw konstrukcyjnych.

17

Recykling wyrobów kompozytowych w energetyce

Brzeziński Henryk, Zawadzka Ewa

Inżynieria Elektryczna

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2022

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nr 9

24--25

PL

Wyroby ze wzmacnianych żywic epoksydowych są masowo stosowane w przemyśle elektrotechnicznym (energoelektrycznym) ze względu na ich niezawodność i dobre parametry użytkowe. Takie materiały to chemo- i termoutwardzalne żywice organiczne (epoksydowe, poliestrowe, poliuretanowe i in.) wypełnione w znacznym stopniu mączkami lub piaskami kwarcowymi (60–70% wag.) oraz włóknem szklanym ciągłym lub ciętym (do 90% wag.), a wyroby z nich produkowane to izolatory, ograniczniki, rury, pręty i maszty, ale też łopaty turbin elektrowni wiatrowych, skrzynki rozdzielnic, obudowy i profile. Taka powszechność wiąże się z dużą i stale przyrastającą ilością odpadów, które nie są biodegradowalne ani (dotychczas) recyklowane na szeroką skalę. Wtórne zagospodarowanie materiałów odpadowych pochodzących z różnych strumieni procesowych (odpad produkcyjny, produkt wadliwy, produkt zużyty) do produkcji wyrobów analogicznych do pierwotnych zmniejszyłoby obciążenie środowiska odpadami składowanymi, pozwoliło zmniejszyć ilość surowców nowo produkowanych i koszty zakupu poprzez zastąpienie ich części recyklatem. Prace prowadzone w dziedzinie technologii kompozytowych w Łukasiewicz – Instytucie Elektrotechniki od 2019 roku ukierunkowane są na recykling odpadów epoksydowych w rozumieniu gospodarki obiegu zamkniętego (GOZ).

18

The Influence of Material Configuration of Fibre-Metal Laminates with Alumina Core on Flexural Strength

Frankiewicz Mariusz, Karoluk Michał, Dziedzic Robert, Timmel Tristan, Scholz Peter

Fatigue of Aircraft Structures

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2022

|

Iss. 14

18--28

EN

Fibre metal laminates (FMLs) consisting of layers made of PA6 polyamide prepregs reinforced with glass and carbon fibres and an aluminium alloy core are the new variant of the other types used by aerospace FML materials such as GLARE or CARALL. By using a thermoplastic matrix, they can be shaped by stamping processes, which allows for a more efficient production process than classical laminating methods such as vacuum bagging. In addition to the improved impact energy absorption efficiency, the metallic core can be utilised to effectively bond the composite part to adjacent metallic structures. This article presents the influence of the material configuration of fibre-metal laminates consisting of continuous fibre-reinforced thermoplastic outer layers integrated with a layer of metallic aluminium alloy inserts - a number of layers, type and direction of reinforcing fibres - on the static and fatigue flexural properties. In this study, eight laminate configurations were prepared using a one-step variothermal consolidation process. The results showed that in the three-point flexural fatigue test, the samples exceeded 106 cycles at stresses <30% of the static bending strength. Laminates with predominantly longitudinally reinforced layers showed the highest fatigue strength among the FML samples analysed. The type of reinforcing fibres and the number of layers were less affected on the analysed mechanical properties.

19

Research of stress concentration at closely placed holes in wing bearing area in anisotropic plater

Maksymovych Marta, Lazorko Aleksandr, Maksymovych Olesia, Dmitriiev Oleh

Diagnostyka

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2022

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Vol. 23, No. 4

art. no. 2022302

EN

In this article effective approach of the study of high-stress concentration at closely placed holes in wing bearing area (in anisotropic plates) is proposed. It is based on the boundary integral equation method with the additional use of the asymptotic method. The simplicity, precision of the approach and the stability of the solution are illustrated in the calculation of stresses in the plate with a circular hole, an elliptical hole, elongated holes, a plate with two closely spaced elliptical holes.

20

Friction brakes in railway vehicles : the phenomenon of friction pairs contact

Szyca Mikołaj

Developments in Mechanical Engineering

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2022

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nr 18(10)

5--13

EN

Rail vehicle brakes have evolved in recent years by applying the first results of research on new friction materials that replace cast iron. The article discusses the phenomena occurring in the friction pairs of rail vehicle brakes in relation to the current issues related to the implementation of composite materials for commercial applications. The article aims to analyze the key aspects of the use of friction brakes in railways and begins research in this field.

PL

Pierwsze rezultaty badań nad nowymi materiałami ciernymi zastępującymi żeliwo spowodowały w ciągu ostatnich lat zmiany hamulców pojazdów szynowych. W artykule omówiono zjawiska występujące w parach ciernych hamulców pojazdów szynowych w odniesieniu do bieżących zagadnień dotyczących wdrażania materiałów kompozytowych do zastosowań komercyjnych. Przeanalizowano kluczowe aspekty w zakresie eksploatacji hamulców ciernych w kolejnictwie, co stanowi wstęp do badań w tym zakresie.