Wyniki wyszukiwania - BazTech

1

Study on Possible Replacement of the Aluminum Spar with a Composite Structure Illustrated with the Case of Agricultural Aircraft

Fałek M., Szymczyk E., Jachimowicz J.

Fatigue of Aircraft Structures

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2017

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Iss. 9

85--99

EN

Composite materials are increasingly being used in aviation. Specific stiffness and strength of composite materials (especially CFRP laminate, sandwich structure) are higher compared to metal alloys. They are beneficial features of materials used in aviation. Mass reduction of aircraft structures (e.g. due to the use of composite materials) contributes to an aircraft’s better performance in terms of its range, top speed and ceiling and consequently causes an increase in airplanes capacity. Moreover, the use of high-strength and lightweight materials in aviation contributes to longer life time and lower exploitation costs. The aim of the paper was the study the possibilities of replacing the aluminum spar of an airplane wing with a composite structure. In order to compare the mass and strength of the aluminum with the composite spar, the global shell and local solid models were created and finite elements analysis was performed. The analysis was carried out for the front spar of the wing of the agricultural aircraft PZL-106.

2

Design and Strength Analysis of Curved-Root Concept for Compressor Rotor Blade in Gas Turbine

Wdowiński W., Szymczyk E., Jachimowicz J., Moneta G.

Fatigue of Aircraft Structures

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2017

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Iss. 9

137--155

EN

The motivation of the article is fatigue and fretting issue of the compressor rotor blades and disks. These phenomena can be caused by high contact pressures leading to fretting occurring on contact faces in the lock (blade-disk connection, attachment of the blade to the disk). Additionally, geometrical notches and high cyclic loading can initiate cracks and lead to engine failures. The paper presents finite element static and modal analyses of the axial compressor 3rd for the original trapezoidal/dovetail lock geometry and its two modifications (new lock concepts) to optimize the stress state of the disk-blade assembly. The cyclic symmetry formulation was used to reduce modelling and computational effort.

3

FEM design of composite - metal joint for bearing failure analysis

Puchała K., Szymczyk E., Jachimowicz J.

Przegląd Mechaniczny

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2015

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nr 2

33--41

PL

Stałe dążenie do uzyskania jak najmniejszej masy samolotu jest powodem stosowania w konstrukcjach lotniczych materiałów o wysokiej wytrzymałości i sztywności właściwej. Wysokowytrzymałe stale, stopy tytanu lub stopy aluminium (np. 2024T3) oraz laminaty kompozytowe (np. CFRP, Glare) są przykładami takich materiałów. Stosowanie różnorodnych materiałów na struktury lotnicze wymusza konieczność łączenia części metalowych z kompozytowymi. Stosuje się różne techniki łączenia pokryć płatowca z elementami usztywniającymi: mechaniczne (połączenia nitowane, śrubowe), adhezyjne (klejenie, okazjonalnie zgrzewanie), hybrydowe (w którym zastosowano kombinacje dwóch różnych metod). W przypadku połączeń mechanicznych konieczne jest wykonywanie otworów, które stanowią miejsca silnych koncentracji naprężeń decydujących o wytrzymałości całej konstrukcji. Połączenia mechaniczne jako stosowane od dziesięcioleci odznaczają się wysokim poziomem niezawodności. Połączenia mechaniczne można wykonywać oraz użytkować w trudnych warunkach środowiskowych. Celem pracy jest projekt mechanicznego połączenia metal-kompozyt oraz analiza niszczenia elementu kompozytowego. Analizowano dwucięte połączenie śrubowe. Przeprowadzono obliczenia analityczne oraz numeryczne.

EN

The constant attempt to obtain as low aircraft mass as possible is the reason for using material of high specific strength (or stiffness) in the aerospace industry. High strength steels, titanium or aluminium alloys (e.g. 2024T3) and composite laminates (e.g. CFRP or Glare) are the examples of such materials. Dissimilar materials in aircraft structures provide a necessity of composite and metallic components joining. Various techniques are used to connect the skin with the stiffening elements: mechanical (riveting, bolting), adhesive (bonding and occasionally welding) and hybrid (where both above mentioned methods are used). Making holes is a necessity for mechanical joints. The holes are the areas of high stress concentrations and they determine load capability of the whole structure. However, mechanical joints used for decades are proved to be reliable. They can be assembled and applied in very rough conditions since they are less sensitive to environmental effects. The goal of the work is development of a mechanical metal-composite joint and failure analysis of the composite part. The double-shear joint is analysed. Both analytical and numerical calculations are performed.

4

Modelowanie wytrzymałościowe i analiza masowo-materiałowa dźwigara skrzydła samolotu rolniczego

Jachimowicz J., Szymczyk E., Łukasiński Ł., Puchała K.

Logistyka

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2015

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nr 4

3726--3733, CD 2

PL

W artykule przedstawiono metodologię obliczeń wytrzymałościowych mającej na celu zamianę dźwigara metalowego na kompozytowy na przykładzie rolniczego samolotu PZL-106 Kruk. Zilustrowano przypadki obciążeniowe oraz wskazano przypadek wymiarujący z odpowiednim rozkładem obciążeń. Pokazano modele wytrzymałościowe segmentu dźwigara. Wykonano obliczenia analityczne oraz analizy numeryczne. Przedstawiono analizę sztywnościowo-masową przykładowych rozwiązań , z analizy których wynika m.in. , że stosując kompozyt węglowy jako materiał dźwigara można zmniejszyć masę o około 69%.

EN

The paper presents a strength analysis methodology intended for replacing the metallic wing spar with a composite one on the example of PZL-106 Kruk agriculture aircraft. Loading cases are presented and dimensioning case with appropriate load distribution is selected. Static strength models of wing spar are studied. Analytical and numerical calculations are performed. The strength-mass analysis for exemplary configurations is presented. This analysis shows that mass of the spar can be reduced by 69% if the D16TN aluminum alloy is replaced with CFRP composite of appropriate configuration.

5

Analiza dwuzakładkowego połączenia adhezyjnego metal–kompozyt

Szymczyk E., Puchała K., Jachimowicz J.

Mechanik

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2014

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R. 87 nr 11

946--949

PL

Omówiono metody łączenia różnorodnych materiałów. Wskazano ich wady oraz zalety. Przedstawiono mechanizm przenoszenia obciążenia pozwalający na zwiększenie wytrzymałości elementu kompozytowego w miejscach połączeń. W oparciu o analogię do połączenia klejowego, przystąpiono do analizy naprężeń stycznych w połączeniu dwuzakładkowym metal–metal oraz metal– –kompozyt. Przedstawiono dwa podejścia stosowane w modelowaniu kompozytu.

EN

Methods of various materials joining are presented. Their benefits and drawbacks are pointed out and analyzed. The load transfer mechanism resulting in increase of the composite material strength in the joint area is presented. Analysis of the shear stress in double-lap in metal-to-metal and in metal-to-composite adhesive joints was carried out by analogy to the adhesive joint. The paper presents two approaches in the composite material modeling.

6

Analysis of load transfer into composite structure

Szymczyk E., Jachimowicz J., Puchała K.

Applied Computer Science

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2014

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Vol. 10, no 3

86--94

EN

The paper presents advantages and disadvantages of metal foils insertion between composite layers. Composites are complex materials of aniso-tropic structure leading to various failure mechanisms. Mechanism of compressive load transfer into composite laminates by shear of the matrix is analysed. The method of improvement compressive strength of laminates is presented according to literature and analysed for a sele-cted case. Simplified models of a laminate structure modified using various metal foils configurations are analysed with MSC.Marc code. Axial stress in prepreg layers and shear stress in adhesive layers are studied.

7

Eksperymentalna i numeryczna analiza procesu instalacji nitu

Korbel A., Szymczyk E., Skorupa A.

Biuletyn Wojskowej Akademii Technicznej

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2013

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Vol. 62, nr 2

181-200

PL

W artykule przedstawiono wyniki badań eksperymentalnych oraz analiz numerycznych MES związane z procesem zakuwania nitu. Analizie poddano stosowane w polskim przemyśle lotniczym nity z łbem kulistym z materiału PA24 oraz blachy ze stopu D16CzATW. Zbadano, jak siła nitowania wpływa na charakterystyczne wymiary zakuwki oraz ekspansję otworu nitowego, a następnie uzyskane wyniki porównano z wynikami analiz MES. Ponieważ dotychczas stosowane metody pomiaru ekspansji otworu mogą być obarczone błędem, opracowano własną metodę pomiaru, cechującą się większą dokładnością. Zbadano, jak przyjęty w analizach MES model materiału nitu wpływa na jakość otrzymywanych wyników. Wykazano, że wierne odtworzenie procesu nitowania w MES wymaga odpowiedniego zdefiniowania modeli materiałowych stosowanych w tych analizach. Ponadto określono wpływ siły zakuwania nitu na rozkład oraz wielkość resztkowych naprężeń promieniowych i obwodowych wokół otworu nitowego.

EN

Experimental results and numerical FE analysis related to the riveting process are considered in the paper. The research has focused on the round head rivet and D16CzATW sheet material used by Polish aircraft manufacturers. The effect of rivet squeeze force on the rivet driven head dimensions and rivet hole expansion was experimentally investigated and the results were compared with the FE results. In view of an insufficient accuracy of hole expansion measurement methods used so far, a novel more accurate measurement technique developed by the present authors has been applied. FE results were obtained for various models of the rivet material. It was shown that an adequate numerical modelling of the rivet installation is conditioned by appropriate assumptions about the constitutive characteristics of the rivet material. The impact of the squeeze force on distributions and values of residual stresses generated by riveting was also determined.

8

Wpływ długości nitu na naprężenia własne w połączeniu nitowym

Szymczyk E., Puchała K.

Przegląd Mechaniczny

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2012

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nr 7-8

59-64

PL

Wytrzymałość połączeń nitowych zależy od czynników konstrukcyjnych, technologicznych i materiałowych. Nity tak jak wszystkie części mechaniczne produkowane są z określoną tolerancją, a ich wymiary zawierają się w ustalonych granicach. W artykule przedstawiono analizę wpływu czynnika technologicznego, jakim jest długość nitu, na naprężenia własne w połączeniu. Obliczenia wykonano dla blach ze stopu aluminium 2024T3, stosowanego na pokrycia lotnicze, łączonych nitami z materiału PA25 o podwyższonej wytrzymałości. Analiz´ stanu naprężenia przeprowadzono dla trzech długości nitu. Zwrócono uwagę na naprężenia styczne, które mogą powodować pękanie zakuwek.

EN

The load carrying capacity of riveted joints depends on many structural, manufacturing and material factors. Rivets, like all mechanical parts, are produced with certain tolerance, therefore their dimensions are enclosed in fixed limits. The paper presents an influence of such a technological factor as a rivet length on a residual stress state in the riveted joint. Numerical calculations were performed for sheets made of 2024T3 alloy commonly used in aircraft fuselages joined together with rivets of high-strength PA25 alloy. The analysis of residual stresses is performed for three different rivet lengths. The shear stress field which tends to cause cracking of the formed rivet head is taken into account.

9

Some aspects of dynamic riveting simulations

Szymczyk E., Jachimowicz J., Puchała K.

Journal of KONES

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2012

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Vol. 19, No. 1

423-430

EN

Riveting is a commonly used (especially in aircraft structures) method of joining metal and composite components. The methods of forming solid shank rivets can be classified in two types: static and dynamic. The static method is the most efficient one. Regrettably, its application is limited. A popular upsetting tool used in an aircraft is a pneumatic riveter. The rivet driving requires a few hammer strokes. The total stress in a riveted joint depends on the residual and applied stress. Residual post-riveting stress fields are widely accepted to have a beneficial influence on the fatigue life of aircraft structures. The analysis is carried out for a solid mushroom rivet (made of PA25 alloy) joining two sheets (made of 2024T3 alloy). Nonlinear dynamic simulations of the upsetting process are carried out. Simulation of the riveting process is significantly influenced by a material model. The numerical calculations are performed for three different cases of upsetting described by the formed rivet head diameters 1.4d, 1.5d and 1.6d, respectively. The rivet head diameter and, consequently, the residual stress state depend on hammer stroke energy. It has a significant influence on a plastic region around the rivet hole, whereas the influence of a number of strokes can be neglected. The strain rate in both local and global (average) formulation is analysed in the paper. For one hammer stroke, the global strain rate of the rivet shank is about 1.0 thousand per second. The local strain rate is about two times greater than the global one, so a strain rate factor has an effect on the residual stress state. For a few hammer strokes, the strain rate is lower than for one stroke; however, it increases a little in each stroke. The hole deformation can be treated as a function of the internal energy of the sheet. The lower total energy of the part the greater influence of the strain rate on the internal energy is observed.

10

Friction coefficient determination based on the results of ball – on - flat test

Szymczyk E., Jachimowicz J., Prasek Ł.

Journal of KONES

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2012

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Vol. 19, No. 1

415-422

EN

The interaction of contacting surfaces in relative motion is basic for every engineering design. The transmission of load from one rubbing surface to its mating surface under conditions of dry contact is taken into account. Microlocal or global models of friction are used to describe this phenomenon. In global approach, frictional force is proportional to normal load. A coefficient of external friction depends on the type, shape, and precision of finishing the surfaces of mating elements. The aim of the paper is analysis of a friction coefficient for 2024T3 aluminium alloy during cyclic tangential loading. Experimental tests are carried out on a ball-on-flat wear-testing machine Ducom. Tests of reciprocating friction are carried out using the following friction pairs of specimens: the ball specimen is made of high strength aluminium alloy PA25 and the plane specimen is made of 2024T3 alloy. Finally, graphs of temporary friction coefficients versus time in the form of fluctuated periodical functions are obtained. Two phases of friction are detected. However, during the first stage, the friction coefficient is relatively small while in the second period it rapidly increases and tends to become more irregular. Static and dynamic friction coefficients are estimated. In order to determine the dynamic coefficient the Discrete Fourier Transformation is used. The calculation of the dominant amplitude (corresponding to test frequency) of the studied functions is possible due to this method. An increase of the friction coefficient with an increase of normal load is observed. A cladding layer also causes an increase of friction, especially in the second phase.

11

About mechanical joints design in metal - composite structure

Puchała K., Szymczyk E., Jachimowicz J.

Journal of KONES

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2012

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Vol. 19, No. 3

381-390

EN

Riveting is still one of the main joining methods of thin-walled aircraft structures. Such features as simplicity of implementation, possibility of two different material connection (e.g. metallic with non-metallic ones) and the fact that is it a well-known (reliable) method causes popularity of riveting. The never-ending attempt to obtain as low mass as possible (mainly to reduce fuel consumption) is the reason for using material of high specific strength in the aerospace industry. High strength titanium or aluminium alloys (e.g. 2024T3) and composite laminates (e.g. CFRP or Glare) are examples of such materials. The article deals with methods of connecting various materials. The paper presents advantages and disadvantages of different/selected connection types. Strength prediction and failure modes of mechanical joints are described for metallic as well as for composite components. Composites are complex materials having an anisotropic structure (and anisotropic mechanical properties) leading to various failure mechanisms. Main principles for appropriate joint design of composite laminate panels (laminate configuration and typical/specific geometrical dimensions) are indicated/specified. The bearing failure mechanism is accepted to be a safe progressive one. Mechanism of bearing (generally compressive) load transfer into composite laminates by shear of the matrix is analysed. Some examples of improvement bearing strength of laminates are presented according to literature. On the base of presented examples and bearing load transfer analysis, some conclusions for an appropriate solution of this problem are drawn.

12

Numerical Analysis of Material and Manufacturing Factors in Riveted Joints Under the Imperja Project

Szymczyk E., Bogusz P., Sławiński G., Jachimowicz J.

Fatigue of Aircraft Structures

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2012

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Iss. 4

100--113

EN

The aim of the project was to improve fatigue performance of riveted joints in airframes. Fatigue strength of a joint depends on structural, material and manufacturing factors. The project involved numerical and experimental analysis of material factors and manufacturing imperfections. The paper deals with the analysis of material structure and properties by means of the optical and SE methods. Static monotonic tests for sheet and rivet materials were carried out. ARAMIS optical system was used for the study of deformation and strain fields in the material during loading. This tool offers the possibility of a non-contact measurement with 3D image correlation methods (digital image correlation, DIC) using high-resolution digital CCD cameras. In ductile materials (such as aluminium alloy), subjected to appropriate loading conditions, voids may form, which grow and coalesce leading to crack formation and potential failure. A micro crack may be initiated at the inclusion particles and then voids grow around it. Experimental studies showed that these processes are strongly influenced by hydrostatic stress (Gurson’s material model). SEM analysis of material structure was carried out after performing static tests. In the paper, the authors present the influence of a material model on the results of numerical simulation of the tensile loaded samples with open and riveted holes. The application of Gurson’s material model allows observation of crack growth in the sample cross-section and determination of the sheet rupture as the moment when constraint force decreases to zero (material separation occurs).

13

The Influence of Riveting Process on Sheets Fatigue Life – the Stress State Analysis

Szymczyk E., Godzimirski J.

Acta Mechanica et Automatica

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2012

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Vol. 6, no. 1

74-81

EN

The paper deals with estimation of a stress concentration factor in the hole area during tensile loading. The load carrying capacity and fatigue performance of sheet samples (made of 2024 aluminium alloy) with open and riveted holes are compared. Tests confirm the insignificant influence of riveting on ultimate strength, however, it strongly affects fatigue life. The material cold working around the hole causes a decrease in maximum principal stress values as well as stress concentration moves away a few millimetres (about half a rivet radius length) from the hole. During tensile loading the maximum stress values increase slower around the riveted hole than at the open one and consequently in the former case the yield stress is achieved later.

14

Zjawisko frettingu w konstrukcjach lotniczych

Jachimowicz J., Kaniowski J., Kozłowski P., Moneta G., Szymczyk E.

Prace Instytutu Lotnictwa

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2010

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Nr 4 (206)

36-58

PL

Zmęczenie cierne często jest przyczyną przedwczesnego zniszczenia zmęczeniowego konstrukcji. Dla ilustracji tego zjawiska wybrano przykłady obiektów lotniczych, których trwałość została istotnie zmniejszona z powodu wystąpienia tego efektu. Są to między innymi struktura skrzydła samolotu i wirnik silnika lotniczego.

EN

Friction fatigue is often a cause of premature fatigue destruction of a structure. The examples of aviation objects, which fatigue durability was reduced because of this effect, were chosen to illustrate this phenomenon. These include a structure of an aircraft wing and a rotor of an air engine.

15

Wpływ wybranych czynników konstrukcyjnych na rozkład naprężeń w zakładkowym połączeniu nitowym

Szymczyk E., Sławiński G., Jachimowicz J., Derewonko A.

Mechanik

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2010

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R. 83, nr 2

115-117

PL

Analizowano wpływ lokalnej zmiany grubości blachy na rozkłady i wartości maksymalnych naprężeń oraz stref naprężeń plastycznych wokół otworów. Wyznaczono również siły przenoszone przez nity oraz blachy w trakcie rozciągania nitowego połączenia zakładkowego.

EN

Discussed are effects of local change of metal sheet thickness on the maximum plastic strain in the material surrounding the holes. The loads as carried over by the rivets and by the metal sheet material in a lap type river joint during tension test are determined.

16

The influence of residual stress fields and sheet thickness on stress distributions in riveted joint

Szymczyk E.

Journal of KONES

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2010

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Vol. 17, No. 1

441-448

EN

Riveting is a traditional, but still popular (particularly in aviation) method of joining metal and composite elements. The residual stress and plastic strain states occur in the joint after the riveting process. The total stress aperienced by the material at a given location within a component depends on the residual and applied stress. Residual post-riveting stress fields are widely accepted to have a significant influence on the fatigue life of aircraft structures. The single lap riveted joint consisting of two sheets and three rows of rivets are analysed. Two specimens are taken into consideration: sheet width and pitch distance are equal to 10.5 mm and rivet diameter is equal to 3.5 mm in the former case whereas 25 mm wide sheets and 5 mm rivet diameter are used in the later case. Distance between rivets (pitch length) and sheet width are equal to 3 or 5 rivet diameters. Materials used in riveted joints are subjected to plastic deformation. The rivet (PA24) and the sheet (2024T3) aluminium alloys are described using piecewise linear material models. The yield stress for the multiaxial state is calculated using the von Mises yield criterion. The paper deals with analysis of the pitch length and sheet thickness influence on stress fields. Stress concentrations around the holes in the rivet row and its distribution between rows are calculated. Models with and without residual stresses are taken into consideration. Local change of the sheet thickness causes a decrease in secondary bending of the joint. This is a result of a small increase in bending between the rivet rows and a simultaneous decrease in maximum bending stress values.

17

Numerical study of the influence of shape imperfections on residual stress fields in a rivet hole

Sławiński G., Niezgoda T., Szymczyk E., Jachimowicz J.

Journal of KONES

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2010

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Vol. 17, No. 2

427-434

EN

The paper deals with the numerical analysis on residua! stress and strain fields in a rivet hole. This stage of study concerns improving of the fatigue performance of riveted joints in an airframe. Riveting, particularly in aviation, is a traditional but still commonly used method of joining sheet metal components. Aircraft structures are thin-walled ones, with coverings made of thin sheets stiffened by stringers, frames or ribs. Sheets are typically assembled by a multiple rivet or bolt joints. Rivets and bolts are also used to joint sheets and stiffeners. Therefore, fatigue resistance of the aircraft structure depends on tens of thousands or even hundreds of thousands r ivet joints, which are used to build it. The local numerical models of the joint are considered with regard to the aim introduced in the paper. Numerical FE simulations of an upsetting process are carried out using the LS-DYNA code. Three-dimensional numerical models are used to determine the resulting stress and strain fields at the mushroom rivet and around the hole. This type of problem requires the use of contact between the elements assembled and non-linear geometrie and elasto-plastic multilinear materiał models to simulate the behaviour of the rivet and sheets. The influence of shape imperfection on strain and stress states is studied.

18

Numerical modelling of a selected part of the airplane fuselage

Szymczyk E., Orzyłowski M.

Journal of KONES

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2010

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Vol. 17, No. 2

459-465

EN

Analysis of a riveted lap joint, the part of M-28 Skytruck fuselage, is presented. The aim of the paper is a proper choice of finite element mesh parameters (shape and density) around the rivet hole as well as a study of the influence of different sheets thickness on secondary bending. Riveting still remains the most popular method of joining metal and composite parts of the aircraft structure. During the operation (service) the severe stress concentrations and the effects such as fretting and secondary bending occur, thus reducing fatigue life. The specimen consists of two thin sheets (0.6 and 1.2 mm thick) stiffened with a 3 mm thick frame. The parts are connected by 14 rivets (3.5 mm diameter) and 8 rivets (3 mm diameter). Overall specimen dimensions are following: length 682 mm, width 136 mm, rivets pitch 17 mm. The riveted joint is subjected to a tensile load. The analysis of large parts of structures like fuselages, wings or multi-row riveted specimens can be performed using global shell models. The correct stress state in global modelling can be obtained by taking into consideration the hole in the sheet, the rivet axis (as a rigid or beam element) and contact elements between the rivet and the hole as well as between the sheets. Deformation of the joint and stress state are calculated. Large difference between sheets thickness causes non-physical deformation of the rivet cross sections. Proper deformations of the joint are obtained by increasing stiffness of those sections in a thinner sheet. Results are compared with an experimental investigation and applied to estimations of specimen fatigue life.

19

Wpływ luzów geometrycznych na stan naprężenia w otoczeniu nitu grzybkowego

Sławiński G., Szymczyk E., Niezgoda T., Jachimowicz J.

Górnictwo Odkrywkowe

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2010

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R. 51, nr 3

29-32

PL

W artykuleprzedstawiono wyniki symulacji numerycznych dotyczących wpływu wybranych imperfekcji geometrycznych naprężenia w otoczeniu nitu. W trakcie spęczania nitu do łączonych blach wprowadzane są naprężenia własne, których przekracza granicę plastyczności. Zjawisko to wpływa na poprawę trwałości zmęczeniowej połączenia. Jednak można się spodziewać, że niedokładności wykonania mogą wpłynąć na pogorszenie wytrzymałości połączenia nitowego.

EN

This paper deals with the numerical FE simulation of the geometrical imperfections influence on the residual stress fields around the rived hole. The residual stress state occurs in the rivet hole after the riveting process exceeds the yieldstress level. It has significant influence on the fatigue life improvement of aircraft structures, however, some geometrical imperfections can reduce the strength of the riveted joint.

20

Numeryczna symulacja dynamicznego procesu spęczania nitu grzybkowego z kompensatorem

Sławiński G., Derewońsko A., Jachimowicz J., Niezgoda T., Szymczyk E.

Biuletyn Wojskowej Akademii Technicznej

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2010

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Vol. 59, nr 1

61-74

PL

W trakcie spęczania nitu do łączonych blach wprowadzane są naprężenia wstępne, których wartość przekracza granicę plastyczności i które zależą od sposobu formowania zakuwek. Zjawisko to wpływa na wzrost trwałości zmęczeniowej połączenia. W artykule przedstawiono numeryczną analizę dynamicznego procesu zakuwania nitu przy zastosowaniu tzw. prostej metody nitowania. Analizy przeprowadzono przy zastosowaniu metody elementów skończonych za pomocą systemu LS-Dyna. Obejmowały one nieliniowości materiałowe oraz zjawiska kontaktowe z tarciem w trakcie procesu spęczania nitu.

EN

This paper deals with the numerical FE simulation of the dynamic riveting process of a mushroom rivet with a compensator. The riveting has remained a traditional and the most popular parts joining method in aircraft structures for many years. The residual stress state appears at the rivet hole after the riveting process, which improves the joint's fatigue behaviour. Numerical FE simulations of the upsetting process are carried out using the Ls-Dyna code. The contact phenomena with friction and nonlinear material model are analysed.