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1

Experimental study of nanocomposite hybrid adhesive-rivet joints

Nabibi Nabard, Ramezani Shadi

Archives of Civil and Mechanical Engineering

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2021

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Vol. 21, no. 3

337--365

EN

The wide range of rivets usage goes back to the processes of manufacturing and repairing an aircraft fuselage. When it comes to structural joints, adhesive bonding is said to have some merits which overshadow other joining methods, such as bolting, riveting, and welding. Today, the applications of structural adhesives do not end in aerospace, but they also are ideal for the automotive industry, where the need is to join plates of dissimilar adhesives to produce lightweight car bodies. The hybrid joints also are one of the methods of joining different parts of the machine in a durable way in which some benefits such as the significant tensile strength, the dissipated energy, and higher reliability during long-term working stand out. In this research, the effect of rivets layout on strength and failure of nanocomposite rivet and hybrid adhesive-rivet joints through two experimental and numerical methods was evaluated. Also, using the artificial neural networks method, force–displacement curves for specimens were obtained. The results of the experimental tests and the finite element analysis showed that as the number of rivets increased in the joint of the nanocomposite components, the strength of the joint increased. The layout of the rivets has a significant effect on the strength of the rivet joint. According to the performed experiments for achieving the efficient strength in the hybrid joints for the nanocomposite plates, since the strength of the adhesive is very effective, adhesive selection and the appropriate number of rivets are the key factors. The fracture modes in the internal plates of nanocomposite joints (adhesive, rivet, and adhesive-rivet joints) were observed as follows: net-tension, bearing, shear-out, crack propagation, tearing, and shear in adhesive layers. Besides, the numerical model of the work is done using ABAQUS software. The results of software simulation in the numerical model are compatible with the experimental method’s findings. However, the agreement between the results of experimental and neural network methods is higher. Owing to the results of experiments, the polypropylene nanocomposite as well as the appropriate jointing method can be put forward in the structures of the automotive industry.

2

Optimal capacity planning of renewable distributed generation in active distribution networks to reduce greenhouse gas emissions

Olivas J. L. M., De Faria Jr. H., Sousa T., Belati E. A.

Przegląd Elektrotechniczny

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2017

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R. 93, nr 4

135--139

EN

This work presents an evaluation of the maximum capacity of renewable distributed generation that can be connected to active distribution networks to minimize the greenhouse gas emissions of the electric network. The study aimed at obtaining a methodology applicable to active distribution networks with characteristics of variable generation and demand in order to reduce greenhouse gas emissions from electric power generation activities. The formulation of the methodology is based on an optimal power flow model incorporating special system controls.

PL

W artykule rozważa się maksymalna pojemność odnwialnych źródeł energii rozproszonej która może być dołączona do aktywnej sieci rozdzielczej dla zminimalizowania emisji gazów cieplarnianych. Metoda polega na modelu optymalnego przepływu mocy uwzględniającym sterowanie systemem.

3

Modern Electrical Power Source on New System of Distributed and Renewable Energy Sources

Szymański Z.

Przegląd Elektrotechniczny

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2015

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R. 91, nr 6

80-83

EN

This paper presents some solutions of modern renewable energy system applied actually in dissipation energy source. To provide high quality voltage is applied an additional energy storage, made from super capacitor and bidirectional DC/DC convert. Integration of solar battery panels or renewable wind energy system is provided via DC link of the variable speed decoupled autonomous generation system. Results of computer simulation and laboratory experiments are presented in the paper.

PL

W artykule przedstawiono przegląd nowoczesnych rozwiązań systemów rozproszonej energii. W celu uzyskania energii o odpowiedniej jakości należy zastosować superkondensatory współpracujące z dwukierunkowym przemiennikiem częstotliwości. W artykule zamieszczono wyniki obliczeń oraz badan laboratoryjnych systemu baterii słonecznych oraz wiatraków energetycznych.

4

System wielkości charakteryzujący potencjalną i oddzieloną cząstkę zużycia tribologicznego

Sadowski P.

Tribologia

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2011

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nr 6

183-190

PL

Wyróżniono dwa rodzaje cząstek zużycia: oddzieloną i potencjalną. Przedstawiono system wielkości dający kompleksową charakterystykę geometryczną i fizyczną potencjalnej i oddzielonej cząstki zużycia. Charakterystyki te opisano funkcjami wielkości możliwych do uzyskania z badań eksperymentalnych. Wprowadzono wielkość krytycznej zakumulowanej energii właściwej i podano przykłady uzyskanych wartości dla przeprowadzonych badań.

EN

Two types of wear particles are distinguished: separated and potential. The research presents a system of values that gives comprehensive geometrical and physical characteristics of potential and separated wear particles. These characteristics describe functions of values obtainable from experimental studies. Introduced value critical accumulated specific energy and gives examples of achieve values for the tests.

5

Energia akumulowana i rozpraszana w procesie zużywania ściernego

Sadowski P.

Tribologia

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2008

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nr 4

41-49

PL

Pracę tarcia wyrażono jako sumę dwóch składowych - energii akumulowanej i rozpraszanej. Opracowano metodę ich określania. Uwzględniono: pracę tarcia, twardość materiału, obciążenie normalne pary tarciowej, liniową intensywność zużywania, wymiary powierzchni nominalnej styku ciał oraz parametr chropowatości powierzchni tarcia Ra. Wyznaczono współczynnik akumulacji energii. Przytoczono wybrane przykłady obliczeń składowych bilansu energii dla mechanizmu zużywania ściernego metali.

EN

Friction work is expressed as a sum of two parts - accumulative and dispersed energy. The method of determining them was prepared. The following are considered: friction work, hardness of material, standard load of friction pair, linear intensity of wear, size of nominal surface of objects contact, and the parameter of the roughness of surface friction Ra. The coefficient of energy accumulation is calculated. Selected examples are given of parts of the energy balance calculations for the mechanism of metals abrasive wear.

6

Inteligentny autonomiczny system elektroenergetyczny integrujący rozproszone źródła i zasobniki energii odnawialnej

Nowakowski A., Lisowiec A., Kołodziejczyk Z.

Nowa Elektrotechnika

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2008

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nr 6 (46)

40--47

7

Laboratory research of the controllable hydraulic damper

Konieczny J., Kowal J., Pluta J., Podsiadło A.

Engineering Transactions

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2006

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Vol. 54, iss. 3

203-221

EN

The main focus is on the hydraulic shock absorbers employed in vehicles, in the context of parameters associated with the damping force control for the given direction of action and with the energy dispersion. Two types of shock absorbers are examined: those with constant and variable parameters of damping force adjustment. Shock absorbers that were subject to research investigations included a commercially - available shock absorber with fixed parameters and an experimental absorber with variable parameters. The paper summarises the problems experienced during modelling of hydraulic shock absorbers when the equivalent damping ratio is sought. Damper properties and the methods of determining them are outlined. The laboratory tests performed on these shock absorbers are considered in more detail and relevant characteristics are provided for the sake of comparison. The reasons why shock absorbers with fixed parameters have been in widespread use for many years are now investigated, highlighting the aspects which prompt the research work on shock absorbers with variable parameters.

8

Renewable energy sources

Mazurek B.

Prace Naukowe Instytutu Podstaw Elektrotechniki i Elektrotechnologii Politechniki Wrocławskiej. Konferencje

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2003

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Vol. 39, nr 14

5-8

EN

Burning of coal in energy production causes a considerable degradation of natural environment, hence a tendency occurs to move over to less harmful energy sources - gas, crude oil and biomass. Renewable clean energy sources, such as water power, wind and solar energy gain on importance, and their share in overall energy balance must constantly increase. A new philosophy of the development of power industry is represented by the so called distributed (decentralized) power industry, consisting of a number of small power plants localized near and user. In the nearest future an urgent need will emerge for mobile power units with several to some dozen of megawatts output, mounted on tracks. These units will be used in case of disasters and failures of power nets.