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Ed.itors Teodor Atanac.kovi6 Dragan Spasic SrboljubSimi6

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Page 1: Ed.itors Teodor Atanac.kovi6 Dragan Spasic SrboljubSimi6is.fink.rs/podaci/Nenad_Grujovic/52/Palic Subotica-Automatic... · Nenad Markovic FAILURE MECHANISM FOR LONGITUDINALY STIFFENED

Ed.itors

Teodor Atanac.kovi6 Dragan Spasic SrboljubSimi6

Page 2: Ed.itors Teodor Atanac.kovi6 Dragan Spasic SrboljubSimi6is.fink.rs/podaci/Nenad_Grujovic/52/Palic Subotica-Automatic... · Nenad Markovic FAILURE MECHANISM FOR LONGITUDINALY STIFFENED

Proceedings

IConSSM- 2009 2nd International Congress

. of Serbian Society of Mechanics

Palie (Subotica), 1-5 June 2009

Editors

Teodor Atanackovic . Dragan Spasic Srboljub Simic

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2nd International Congress ofSerbian Society of Mechanics (IConSSM 2009)

Editors Teodor Atanackovic Dragan Spasic Srholjub Simi6 .

Computer editing Srboljub Simi6

Press "Indeks", Novi Sad

Circulation 250 copies

CIP - Km:an;orH33.QHja y ny6.J:noomBjR DR6JmOTeKa Mamne cpncKe, HOBR Ca,n:

531/534(082)

INTERNATIONAL Congress of Serbian Society of Mechanics (2 ; 2009 ; PaliC)

Proceedings / 2nd International Congress ofSerbian Society of Mechanics (IConSSM 2009), Palie (Subotica), 1-5 June 2009; editors Teodor Atanackovic, Dragan Spasic, Srboljub Simic. - Beograd: Srpsko drustvo za mehaniku ; Novi Sad : Fakultet tehnickih . nauka, 2009 (Novi Sad: Indeks). - XLII, 182 str. : ilustr. ; 25 em

TiraZ 250. - Str. III: Preface I the editors. - Bibliografija uz svaki reid.

ISBN 978-86-7892-173-5

a) 11exaHHKa-36opHHUH

COBISS.SR-ID 239743495

Published by Serbian Society ofMechanics, Belgrade Faculty ofTechnical Sciences, Novi Sad

a

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PREFACE

The present volume contains plenary lectures and papers of yeung authors, competing for the prize "dr Rastko Stojanovi6", presented at the Second International Congress of Serbian Society of Mechanics, held at Pali6 (Subotica) during the period 1st_5th June 2009. The Congress was organized by the Serbian Society of Mechanics. The aim of the Congress is presentation of original high level work, at the forefront of research, in various areas of Theoretical and Applied Mechanics.

During the Congress 123 papers were presented, grouped in four traditional sections: General Mechanics, Fluid Mechanics, Mechanics of Solid Bodies and Interdisciplinary and Multidisciplinary Problems. Moreover, three mini-symposia are held: (Ml) MM-:qc Fractional Calculus and Applications, (M2) Computational Methods in Structural Analysis and Fracture Mechanics and (M3) Computational Biomechanics. In addition,8 invited plenary lectures were presented by the authors from France, Germany. Italy, Serbia, Slovakia and United States.

The Editors would like to thank all the· authors of the papers for their active participation during the Congress, the reviewers of the papers, the members of the Scientific and Organizing Committee, the members of the Executive Committee of the Serbian Society ofMechanics, and the distinguished invited lecturers who kindly accepted the invitation to come to Congress and helped make it success.

Special thanks are also due to those organizations which supported financially this Congress: Serbian Society of Mechanics, Engineering Chamber of Serbia, Ministry of Science ofSerbia, Provincial secretariat for Science and Technological Development of the Province ofVojvodina. and Municipality ofSubotica ..

Palic, June 2009 The Editors: Teador Atanackovi6 Dragan Spasi6 SrboljubSimi6

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· 2nd International Congress of Serbian Society of Mechanics IConSSM 2009, Palie (Subotica), 1-5 June 2009

Scientific Committee

Nikola Hajdin (Belgrade, Serbia) Vladan Bordevi6 (Belgrade, Serbia) Teodor Atanackovic (Novi Sad, Serbia) Bofidar Vujanovic (Novi Sad, Serbia) Borde Bukic (Novi Sad, Serbia) Borde Zlokovic (Belgrade, Serbia) Robin Tucker (Lancaster, England) Ingo MUller (Berlin, Gennany) Gerard Maugin (Paris, France) Anthony Kounadis (Athens, Greece) John Katsikadelis (Athens, Greece) Joseph Zarka (palaisea.u, France) Alexander Seyranian (Moscow, Russia) Chi Chow (Michigan, United States) Jovo Jaric (Belgrade, Serbia) Milo§ Kojic (Kragujevac, Serbia) Milan Mi6unovic (Kragujevac, Serbia)

Organizing Committee

Teodor Atanackovic (Novi Sad, Serbia) Drag!!Il Spasic (Novi Sad, Serbia) Srboljub Simic (Novi Sad, Serbia)

iv

Stevan Maksimovic (Belgrade, Serbia) Vladimir Dragovi6 (Belgrade, Serbia) Ranislav Bulatovic (podgorica, Montenegro) Milos Nedeljkovic (Belgrade, Serbia) Nikola Mladenovic(Belgrade, Serbia) Vladimir Stevanovic (Belgrade, Serbia) Stojan Sedmak (Belgrade, Serbia) . Katica (Stevanovic) Hedrih (NH, Serbia) . Ratko Pavlovic (Nis, Serbia) Branislav Borovac (Novi Sad, Serbia) Valentin Glavardanov (Novi Sad, Serbia) Dragoslav J<uzmanovi6 (Belgrade, Serbia) Dragoslav Sumarac (Belgrade, Serbia)

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CONTENTS

Contents of CD IConSSM 2009 Vl1

Tecnhical Program xxi

Plenary Lectures 1

Andreas Acrivos THE RHEOLOGY OF CONCENTRATED SUSPENSIONS OF NONCOLLOIDAL PARTICLES: LATEST VARIATIONS ON A THEME BY ALBERT EINSTEIN

3

O.T. BIubns EULERIAN ELASTOPLASTICITY: BASIC ISSUES AND RECENT RESULTS

5

Tommaso Ruggeri MULTI-TEMPERATURE MIXTURE OF FLUIDS

31

Igor Podlubny FRACTIONAL DERIVATIVES AND FRACTIONAL DIFFERENTIAL . EQUATIONS: HISTORY, METHODS, AND APPLICATIONS

51

GCnjfd Iooss WATER-WAVES AND REVERSIBLE SPATIAL DYNAMICS

53

K~~ APPLICATION OF BIOMECHANICAL MODELING FOR PATIENT-SPECIFIC ARTERY AND ATHEROGENESIS DISEASE AND PREDICTIVE MEDICINE TREATMENT

~

Chi L. Chow and Yong Wei VISCOPLASTIC THEROMECHANICAL FATIGUE DAMAGE

87

B. Gajic DYNAMICS AND GEOMETRY OF INTEGRABLE RIGID BODY MOTION

103

Papers of Candidates for "dr Rastko Stojanovic" Award 129

Milos Zivanovic SCLERONOMIC MECHANICAL SYSTEMS IN DECOMPOSITION MODE

131

N.M. Grahovac GENERALIZED ZENER MODEL IN THE ANALYSIS OF FREE VIBRATION OF A VISCOELASTIC OSCILLATOR

145

D. Zorica FORCED OSCILLATIONS OF A ROD MADE OF VISCOELASTIC MATERIAL OF FRACTIONAL DERIVATIVE TYPE

155

v

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M.M.Zigic VISCOELASTIC RESPONSE OF THE HUMAN HAMSTRING MUSCLE DURING A RAMP-AND-HOLD TYPE OF EXPERIMENT

165

D. Petrovic MODELING OF NANOCOATING SELF-HEALING PROCESS USING DISSIPATIVE PARTICLE DYNAMICS (DPD) METHOD

175

vi

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CONTENTS OF CD IConSSM 2009

Plenary Lectures

poOl Andreas Acrivos THE RHEOLOGY OF CONCENTRATED SUSPENSIONS OF NONCOLLOIDAL· PARTICLES: LATEST VARIATIONS ON A THEME BY ALBERT EINSTEIN

P-02 O.T.Bruhns EULERIAN ELASTOPLASTICITY: BASIC ISSUES AND RECENT RESULTS

P-03. Tommaso Ruggeri MULTI-TEMPERATURE MIXTURE OF FLUIDS

P-04 Igor Podlubny FRACTIONAL DERIVATIVES AND FRACTIONAL DIFFERENTIAL EQUATIONS: mSTORY, METHODS, AND APPLICATIONS

P-OS Gerard Iooss WATER-WAVES AND REVERSIBLE SPATIAL DYNAMICS

P-06 N. Filipovic APPLICATION OF BIOMECHANICAL MODELING FOR PATIENT-SPECIFIC ARTERY AND ATHEROGENESIS DISEASE AND PREDICTIVE MEDICINE TREATMENT

P-07 Chi L. Chow and Yong Wei VISCOPLASTIC THEROMECHANICAL FATIGUE DAMAGE

P-OS B. Gajic DYNAMICS AND GEOMETRY OF INTEGRABLE RIGID BODY MOTION

Section A - General Mechanics

A-OI Radomir Mijailovic COEFFICIENT OF RESTITUTION, ELASTO-PLASTIC CHARACTERISTICS OF :COLLISION VEHICLES AND THEIR RELATIONSHIP

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A-02 M.Milinovic, O. Jeremic, A. Karl TIME BEHAVIOR OF NONLINEAR ABSORBER ATTACKING BY SHOCK IMPULSE FORCES

A-03 . Milutin Marjanov ONE SOLUTION OF THE NEWTON'S THREE BODY PROBLEM

A-04 I. Kovacic, Z. Rakaric, L. Cveticanin ON THE MOTION OF THE OSCILLATORS WITH A FRACTIONAL-ORDER RESTORING FORCE

A-05 Milo~ Zivanovi6, Mihailo Lazarevi6 RELATIVE MOTION OF MANWULATOR'S RIGID SEGMENTS WITH RESPECT TO ONE ANOTHER - KINEMATICS

A-06 Mi1o~ Zivanovi6 SCLERONOMIC MECHANICAL SYSTEMS IN DECOMPOSITION MODE

A-07 Mirjana Filipovic ELASTIC DEFORMATION AS A RESULT OF THE TOTAL DYNAMICS OF THE SYSTEM MOVEMENTS

A-08 R. M. Bulatovi6, M. Kane ON THE NON-OSCILLATORY ASYMPTOTICALLY STABLE SYSTEMS WITH PARTIAL DISSIPATION

A-09 Veljko A. Vujici6 NON CONSONANCE IN THEORY OF MECHANICS

A-lO S. Djakovi6, S. Simi6 A NOTE ON STABILITY OF HOVERING MAGNETIC TOP

A-ll Katica R. (Stevanovi6) Hedrih THE OPTIMAL CONTROL IN ENGINEERING SYSTEMS WITH TRIGGER OF COUPLED SINGULARIIES

A-l2 J.Vukovic, A.Obradovic, Z. Mitrovic . OPTIMAL CONTROL OF MECHANICAL SYSTEM MOTION WITH LIMITED REACTIONS OF CONSTRAINTS

viii

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A-13 Bozidar Jovanovic CHAPL YGIN SPHERE

A-I4 Z. Rakaric, M. Zukovic ITERATION METHOD SOLUTIONS FOR OSCILLATORS WITH sign(x)lxla ELASTIC FORCE

A-IS Sh.K.h. Soltakhanov, M.P.Yushkov, S.A. Zegzhda THE THEORY OF MOTION OF THE SYSTEMS WITH HIGH-ORDER NONHOLONOMIC CONSTRAINTS

Section B - Fluid Mechanics

B-OI N. Mladenovic, Z. Mitrovic, S. Rusov NUMERICAL FLOWCOMPUTA TION IN PRESENCE OF MUL TICOMPONENT F.LUID INJECTION

B-02 Ljubi§a Tancic NUMERICAL AND EXPERIMENTAL COMPUTATION MODEL TWO-PHASE FLOW IN THE SMALL ARMS BARREL

B-03 Milo~ M. Jovanovic SIMULATION OF TEMPORAL HYDRODYNAMIC STABILITY IN PLANE CHANNEL FLOW

B-04 Konst. LIOLIOS, Vas. TSIHRINTZISand Diam. KARAMOUZIS A NUMERICAL TREATMENT OF GROUNDWATER FLOW AND CONTAMINANT REMOVAL IN HORIZONTAL WETLANDS

... B-05 Deean Ivanovic, Vladan Ivanovic SHEAR STRESS CONTROL IN HIGH ACCELERATING UNSTEADY INCOMPRESSIBLE BOUNDARY LAYER ON POROUS CONTOUR

B-06 M. Kozic, S. Ristic, Z. Anastasijevic, M. SamardZic OPTICAL AND NUMERICAL VISUALIZATION IN ANALYSIS OF DEFLECTOR ANGLE INFLUENCE ON 2D SUPERSONIC NOZZLE FLOW

B-07 S. Simic, D. Madjarevic STABILITY AND BIFURCATION ANALYSIS OF HYPERBOLIC TRAFFIC FLOW MODEL

ix

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B-08 N. Mirkov, B. Rasuo ON STABILITY OF COLD AIR JET ATTACHMENT TO WALLS

B-09 V. Stevanovic NONCONDENSABLES ACCUMULATION IN NON-VENTED STEAM VOLUMES

..,. ",I)-IV

S. Prica, V. Stevanovic, B. Maslovaric VAPOUR-LIQUID INTERFACE TRACKING AND CONDENSATION INDUCED WATER HAMMER PREDICTIONS

B-ll B. Maslovaric, V. Stevanovic, S. Prica TRANSIENT VAPOUR-LIQUID TWO-PHASE FLOWS IN-LARGE VOLUMES OF STEAM GENERATORS

Section C - Mechanics of Solid Bodies

r ·C-Ol;i- G. Kastratovicand R. Mijailovic

OPTIMUM DIMENSIONS OF TRAPEZOID CROSS-SECTION IN LATTICE STRUCTURES

C-02 Sreten Mastilovic SHORT-TIME AND LONG-TIME ELASTIC RESPONSE OF BRITTLE 2D TRUSS­LATTICES

C-03 Sreten Mastilovic ORDERING EFFECT OF KINETIC ENERGY ON DYNAMIC DEFORMATION OF BRITTLE 2D TRUSS LATICES

C-04 S. Zivkovic, M. Mijalkovic EC3 AND JUS U.E7.121 NORMATIVES ANALYSIS

C-05 I; Angelos LIOLIOS, Asterios LIOLIOS and Anthony POULAKAS

TWO-SIDED NUMERICAL SOLUTION BOUNDS FOR ASEISMIC SHEAR WALLS WITH OPENINGS

C-06 Dragan Kreculj, Bosko RMuo NUMERICAL MODELLING OF THE LAMINATED COMPOSITE STRUCTURES UNDER IMPACT LOADS

x

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C-07 P. Kozie, G. Janevski, R. Pavlovic NUMERICAL DETERMINATION OF MOMENT L Y APUNOV EXPONENT OF THE STOCHASTIC PARAMET,RICAL HILL'S EQUATION

C-08 S. Coric, S.Brcic COLUMN BUCKLING INVESTIGATION OF PLANE FRAMES

C-09 S. Kostic, B. Deretic-Stojanovic CRACKING OF CONCRETE EFFECTS IN CONTINUOUS COMPOSITE BEAM ANALYSIS ACCORDING TO EC4

C-IO J: Jarie, Z. Golubovie, D. Kuzmanovie ON AVERAGE STRESS, COUPLE STRESS AND ROTATIONS IN MICROPOROUS MEDIA

C-ll Lj. Markovic, D. Ruzie ON INVARIABILITY OF THE SOLUTION OF THE GENERAL FORMULA FOR CRITICAL EXTERNAL RADIAL PRESSURE AROUND THE CYLINDRICAL SHELL

C-12 Nenad Markovic FAILURE MECHANISM FOR LONGITUDINALY STIFFENED PLATE GIRDERS SUBJECTED TO PATCH LOAD

C-13 S. Dj. Mesarovie and J. Padbidri GRANULAR MATERIALS: MICROMECHANICS AND MOLTISCALE MODELING

C-14 S. Dj. Mesarovie, H. Radhakrishnan, A. A. Zbib and D. F. Bahr MICORMECHANICS OF CARBON NANOTUBE TURFS

C-15 N. Trisovic, E. E>!indo ABOUT REANALYSIS IN STRUCTURAL DYNAMICS

C-16 N. Boja, G. Briilloiu, R. Ene INTRINSIC APPROXIMATIONS IN THE BAR DEFLECTION ANALYSIS

C-17 Dragan B. Jovanovic LOCAL STRAIN ENERGY AT THE CRACK TIP VICINITY IN DISCRETE MODEL OF MATERIAL'

C-18 J.P. Jarlc, R.D. Vignjevicand S. Mesarovie ON GENERALIZED REYNOLDS TRANSPORT THEOREM

xi

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·1 "

C-19 Ivan Sestak, Bosko S. Jovanovic APPROXIMATION OF UNSTEADY HEAT EQUATION IN THE FORM OF HEMIVARIATIONAL INEQUALITY

C-20 Ljubomir R. Savic THE GENERAL METHOD FOR DETERMINING INFLUENCE FUNCTIONS IN PLANE STRUCTURES

C-21 A.Obradovic, S.Bosnjak, N.Zmic, V. GaSic ANALYSIS OF DYNAMIC BEHAVIOR OF TUE BUCKET WHEEL EXCAVATOR BOOM MODELED AS AN ELASTIC BODY

C-22 T. Maneski, V. Milosevi6 Mitic, N. Andjelic NUMERICAL DYNAMIC ANALYSIS OF THE INFLUENCE OF THE SUPPORTS AND INTERCONNECTIONS OF FIRE ENGINE STRUCTURAL PARTS

C-23 D. Sumarac, Z. Petras1covic VERY LOW CYCLE FATIGUE OF BTRUCTURAL STEEL ELEMENTS

C-24 ,; Tomislav S. Igic, Dragana Tumic, Natasa Markovic ,.

THE NEW PROCEDURE FOR SOLVING ONE EQUATION SYSTEM CLASS IN ENGINEERING PRACTICE·

C-25 V. Marinca, N. Heri§anu . ANALYTICAL APPROXIMATION OF A CONSERVATIVE SYSTEM WITH INERTIA AND STATIC NONLINEARITY

C-26 N. Heri§anu, V. Marinca STUDY ON THE DYNAMIC BEHAVIOR OF AN ELECTRICAL MACHINE ROTOR­BEARING SYSTEM WITH NON-LINEAR SUSPENSION BY OPTIMAL VARIATIONAL ITERATION METHOD

C-27 Katica (Stevanovic) Hedrlh, Julijana D. Simonovic ENERGY ANAL YS OF THE DOUBLE CIRCULAR PLATE SYSTEM

C-28 N. Radie, D. Ruzie INFLUENCE OF INTERACTION BETWEEN LOCAL, DISTORSIONAL AND GLOBAL MODE OF THE LOSS OF STABILITY ON THE DECREASE OF BEARING CAPACITY IN POSTCRITICAL ZONE

xii

t

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C-29 M. Micunovic, Lj. Kudrjavceva, C. Dolieanin ON LOCALIZED NECKING IN THIN SHEETS OF QUASI RATE INDEPENDENT STEELS

C-30 Branislava N. Novakovic, Teodor M. Atanackovic OPTIMAL SHAPE OF A li..tAV-Y- ELASTIC ROD LOADED WITH A CONCENTRATED FORCE AT THE END IN LATERAL BUCKLING

C-31 R. Bogacz, W. Czyczula ON HISTORY DEPENDENT FRICTION MODEL AND ITS APPLICATION

C-32 A. Grillo, D. Logashenko, M.V. Micunovic, G.Wittum STUDY OF A TRANSPORT PROBLf;,MIN A TWO-DIMENSIONAL POROUS MEDIUM

C-33 A. Grillo, M. Lampe, M.V. Micunovic, G . .wittum MODELLING AND SIMULATION OF THERMO-DIFFUSION IN POROUS MEDIA

Section D - Interdisciplinary and Multidisciplinary Problems

D-01 Predrag Elek, Slobodan Jaramaz RAPID EXPANSION OF METALLIC CYLINDER DRIVEN BY INTERNAL EXPLOSIVE DETONATION

D-02 I. Grozdanovic ,N. Buric SYNCHRONIZATION OF IZH BURSTING NEURONS WITH DIFFERENT TYPE'S OF DELAYED COUPLING

D-03 N.Vasovic INFLUENCE OF DELAYED CHEMICAL SYNAPSES AND NOISE ON SYNCHRONIZATION OF HR BURSTING NEURONS

D-04 Ratko Pavlovic, Predrag Kozic, Ivan Pavlovic INFLUENCE OF ROTATORY INERTIA ON DYNAMIC STABILITY OF THE SYMMETRIC CROSS-PLY LAMINATED PLATES

D-05 M. Cosic GLOBAL STABILITY ANALYSIS OF THE SYSTEM FAILURE CRITICAL MECHANISM

xiii

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1 !

D-06 M. Cosic ABOUT THE REQUIRED CAPACITY OF NON-LINEAR DEFORMATIONS OF THE SDOF SYSTEM WITH THE PUSHOVER ANALYSIS

D-07 Milan Milosevic, Vlado Durkovic, Dragoslav Zivani6 ANALYSIS OF INFLUENTIAL PARAMETERS INTERACTION LAUNCHER­MISSILES AND THEIR CONTRIBUTION TO THE HIT DISPERSION ON THE TARGET

D-08 Dragoslav Zivani6, Vlado Durkovic, Milan Milosevic STABILITY OF SELFPROPELED MULTITUBE ROCKET LAUNCHER DURING AND JUST AFTER A ROCKET'S STARTING

D-09 L ; Marko Joo, Mihailo Lazarevic j"i.' FUZZY LOGIC CONTROL OF THE ROBOT WITH THREE DEGREES OF FREEDOM i ;. /i D-I0

PeriSi6 M. Dragovan STOCHASTIC DIFERENTlAL GAME UNDER INCOMPLETE STATE VECTOR INFORMATION

D-U· Gyula Mester POSITION CORRECTION SYSTEM OF WHEELED MOBILE ROBOTS USING ULTRASONIC SENSORS

0-12 M. Chen,H. Zhao, W. Liu, D.P. Sekulic SPREADING OF NANO-COMPOSITES OF LIQUID METALS

D-13 F.L.V. Vianna, H.R.B. Orlande, G.S. Dulikravich ESTIMATION OF THE TEMPERATURE FIELD IN PIPELINES BY USING THE KALMAN FILTER

D-14 Aleksandar Grbovic, Miljana Tanaskovic, Nenad Vidanovic COMP ARATNE ANALYSIS OF THE STRESS DISTRIBUTION ON THE TOOTHLESS ALVEOLAR RIDGE AT THE BOTTOM OF THE COMPLETE DENTURE PROSTHESIS ANt> OVERDENTURE RETAINED WITH MINI IMPLANTS

D-15 Dj. Koruga, S. Miljkovi6, S.Jankovi6 MECHANICAL AND ELECTROMAGNETIC PROPERTIES OF NANOSTRUCTURED WATER

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D-16 L. Matija, D. Kojic, Dj. Koruga SURFACE CHARACTERIZATION OF CARBON .sTEEL BY MAGNETIC FORCE MICROSCOPY

D~17 N. StevanoVic, D.Damian, S. Jankovic, Dj .Koruga GENERATING NANOFLOWS OF BIOFLUID BY IRROTATIONAL VORTEX DURING THE CELL DIVISION

. Mini-symposium Ml - MM-IX Fractional Calculus and Applications

MI-Ol M.P.Lazarevic, Lj. Bucanovic CONTROL ALGORITHMS OF pjlDaTYPE IN PROCESS CONTROL SYSTEMS: NEW RESULTS

MI-02 N. M. Grahovac GENERALIZED ZENER MODEL IN THE ANALYSIS OF FREE VIBRATION OF A VISCOELASTIC OSCILLATOR

MI-03 Katica (Stevanovic) Hedrih, Andjellca N. Hedrih EIGEN MAIN CHAIN MODES OF THE DOUBLE DNA FRACTIONAL ORDER CHAIN HELJX VIBRATIONS

MI-04 Z. VOSOOl FROM PARTICLES TO FIELD: ELECTROMAGNETIC FRACTIONAL APPROACH

MI-05 D.Zorica FORCED OSCILLATIONS OF A ROD MADE OF VISCOELASTIC MATERIAL OF FRACTIONAL DERIVATIVE TYPE

MI-06 M.M.Zigic VISCOELASTIC RESPONSE OF THE HUMAN HAMSTRING MUSCLE DURING A RAMP-ANO-HOLD TYPE OF EXPERIMENT

MI-07 Sanja Konjik, Ljubica Oparnica, Dusan Zorica FRACTIONAL ZENER WAVE EQUATION

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Mini-symposiuJll M2 - Computational Methods in Structural Analysis and Fracture Mechanics

M2-01 Daniela Ristic COMPUTATION MODEL FOR THE ANALYSIS OF GEAR TOOTH ROOTH STRESSES

M2-02 D.Mijuca ON THE RELIABLE AND EFFICIENT THERMAL STRESS FINITE ELEMENT PROCEDURE IN MUL TISCALE ANALYSIS OF SOLIDS

M2-03 Z. Bordevic, S. Jovanovic, V. Nikolic-Stanojevic STATIC AND DYNAMIC ANALYSIS OF HYBRID ALUMINUM/COMPOSITE SHAFT

M2-04 M. Ugrcie JETTING AND JET PENETRATION MODELING AND COMPUTATION

M2-05 S. Posavljak

1· DAMAGE OF AERO ENGINE DISKS IN FUNCTION OF CYCLIC MATERIAL PROPERTIES AND TYPE OF ENGINE START-STOP CYCLES

M2-06 Malobabic Dejan AIRPLANE STRUCTURE COMPONENT OPTIMIZATION PROCESS BY FE METHOD

M2-07 Marko Bojanie STABILITY ANALYSIS OF THIN WALLED STRUCTURES WITH HOLES BY FINITE ELEMENTS

M2-08 Dragi Stamenkovie EVALUATION OF FRACTURE MECHANICS PARAMETERS IN STEAM TURBINE COMPONENTS USING FEM AND J-INTEGRAL APPROACH

M2-09 I. Ilie, S. Maksimovic INITIAL FAILURE ANALYSIS OF MECHANICALLY FASTENED JOINTS IN THE COMPOSITE TUBES UNDER AXIAL TENSION LOADS

M2-10 Vladan Velickovic, Marko Bojanic SIZING OF MODIFIED TOROIDAL CONTAINER FOR LIQUEFIED PETROLEUM GAS ON BASIS OF RESULTS OF NONLINEAR STRUCTURAL ANALYSES

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M2-11 Mirko Kozi6, Katarina Maksimovi6 NUMERICAL SIMULATION OF FIRE IN TUNNEL USING CFD ANALYSIS

M2-12 Maksimovic S., Kutin M., Maksimovi6 K., Vasovic I. CRACK GROWTH ANALYSIS OF NOTCHED STRUCTURAL COMPONENTS UNDER MIXED MODES

M2-13 . Marija Blafic, Stevan Maksimovi6 FINITE ELEMENT ANALYSES OF STRESS INTENSITY FACTORS OF AN ELLIPTICAL SURFACE CRACKS IN A CIRCULAR RODE UNDER TENSION

M2-14 B. Medo, M. Rakin, M. Vratnica, Z. Cvijovic NUMERICAL AND ANALITICAL DETERMINATION OF THE PLASTIC ZONE SIZE ON PRE-CRACKED HIGH-STRENGTH 7000 Al ALLOYS SPECIMENS

M2-15 A. Aidov, G. S. Dulikravich . MODIFIED CONTINUOUS ANT COLONY ALGORITHM

M2-16 Bratica Temelkoska EXPERIMENTAL AND ANALYTICAL METHODS FOR INVESTIGATING OF DYNAMIC STABILITY OF THE PIPELINE SYSTEM AT A TPP IN EXPOSED TO A SEISMIC LOAD

M2-17 I. Ivanovi6, Z. Petrovic and S. Stupar AIRFOIL SHAPE OPTIMIZATION OF A HELICOPTER ROTOR BLADE

M2-18 I. Atanasovska, M. Krivokapic, D.Momcilovic THE FEM SIMULATION OF RAILWAY VEHICLE KINETIC ENERGY ABSORBER

M2-19 .V. Nikolic, C. Dolieanin, D. Dimitrijevic. NUMERICL MODELING OF DYNAMIC BEHAVIOUR OF COMPLEX SYSTEMS

M2-20 C. Dolieanin, V. NikoliC, M. Radojkovic APPLICATION OF NUMERICAL METHODS IN SOLVING THE PROBLEMS WITH GEOMETRICAL DISCONTINUITY

M2-21 G. Jovicic, M. Zivkovic, N. Djordjevic, N. Jovicic, K. Maksimovic NUMERICAL METHODS FOR DETERMINATION OF THE CRACK EXTENSION

M2-22 Slobodanka Boljanovic, Stevan Maksimovic, Mirjana Djuric FATIGUE - SERVICE LIFE PREDICTION AND CRACK CLOSURE EFFECT

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· MJ-02 D. Veljkovic, I. Vlastelica, M. Kojic INFLUENCE OF DIAMETER AND ASYMMETRY ON THE MECHANICAL STRESSES IN ABDOMINAL AORTIC ANEURYSMS

M3-03 N. Filipovi~, D. Nikolic, D. Milasinovic. M. Kojic, V. Tsakanakis, D. Fotiadis PATIENT-SPECIFIC COMPUTER MODEL OF CORONARY ARTERY USING CFD

MJ-04 A. Peulic, N. Zdravkovic, V. Grbovic-Markovic, A. Jurisic-Skevin, N. Filipovic MODELING OF FUNCTIONAL ELECTRICAL STIMULATION

MJ-05 D. Milasinovic, D. Nikolic, A. Tsuda, N. Filipovic PRE- AND POST-PROCESSING OF 3D ALVEOLAR MODELS FOR CFD SIMULATION

M3-06 D.Petrovic MODELING OF NANOCOATING SELF-HEALING PROCESS USING DISSIPATIVE PARTICLE DYNAMICS (OPD) METHOD

M3-07 R. Radakovic, Dj. Kosanic, R. Vulovic, M. Radosavljevic, N. Filipovic MODELING OF IMP ACT FORCE DURING JUMPING ON THE FORCE PLATE

M3-08 B. Stojanovic, M. Zivkovic, R. Slavkovic NUMERICAL INTEGRATION FOR ASSUMED STRAIN FINITE ELEMENTS

M3-09 M. Kojic, N. Kojic, M. Milosevic, A. Grattoni, E.De Rosa, M. Ferrari FINITE ELEMENT MODELING OF DIFFUSION IN NDS DEVICES (NANOCHANNEL DELIVERY SYSTEM)

M3-10 Milos Kojic, Nenad Filipovic, Velibor Isailovic, Ivo Vlastelica, Boban Stojanovic, Dejan . Petrovic, Tijana Djukic, Paolo Decuzzi, Mauro Ferrari APLLICATION OF LOOSE AND STRONG COUPLING FOR FLUID-SOLID INTERACTION IN CREEPIG FLOWS

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.0> . -­ - ­ .~ :- .

Municipality of Subotica

ISBN 978-86-7892-173-5

9 >

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2nd International Congress of Serbian Society ofMechanics (IConSSM 2009) Palic (Subotica), Serbia, 1-5 June 2009 M2-30:1-9

AUTOMATIC ADJUSTMENT OF LOAD STEP FOR CONTACT PROBLEMS BASED ON THE PENALTY METHOD

S. Vulovict, M. Zivkovie.N. Grujovie

I Faculty ofInformation Technology Tadeu~ Ko§cu/lka 63, 11000 Beograd, Serbia e-mail: [email protected] 2 Faculty ofMechanical Engineering, University ofKragujevac, Sestre Janie 6, 34000 Kragujevae, Serbia e-mail: [email protected] J Faculty ofMechanical Engineering, University ofKragujevae, Sestre Janic 6, 34000 Kragujevac, Serbia e-mail: [email protected]

Abstract. In this paper methods to improve numerical simulation of contact problem by penalty method are presented. The nonlinearities of contact, which more is in large derormations inevitably, lead to the use ofan incremental approach. The determination of a load step is a1lways vel)' difficult. The Newton method is generally used to solve contact problems. When too many changes of contact condition occur, the algorithms of Newton Raphson fanlily may not converge. Too many nodes coming into contact simultaneously may cause solution difficulties. Ideally, one node at a time should come into contact. The main idea of developed method is to limit the number of nodes coming during a time step by using a prediction/correction algorithm. The efficiency of the proposed algorithm is illustrated by numerical example.

1. Introduction

The effective application offmite element contact solvers need a high degree of experience since the general robustness and stability cannot be guaranteed. The analysis of contact problems is useful to improving the mechanical properties in the contact region and increasing the safety of contacted components. The aim of this paper is to provide framework for improve contact problems with friction, based on the penalty method. The penalty formulation has the advantage that it is purely geometrically based and therefore no additional degrees of freedom must be activated or inactivated. The contact problems are load history dependent because of the irreversible nature of frictional forces. An automatic incrementation technique of the applied load has been developed and implemented in the algorithm. The size of the applied load increments, automatically chosen by the algorithm, is in general influenced both by the nature of the problem and of the discretization of the bodies involved. A load scale factor is calculated in each contact node pair where a change of contact condition will occur. The change in contact status corresponding to the node pair with the smallest load scale factor is the only change which is accomplished in a certain iteration. The uniqueness of this kind of contact problem with friction has not been mathematically proven for a general case.

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Numerical example is shown to demonstrate that the presented algorithm can be successfully applied to contact problems.

2. Contact kinematics

In general, a contact can occur between: a deformable body and a rigid obstacle; between two deformable bodies or as a self-contact. In this paper a contact between two deformable bodies is considered. As the configuration of two bodies coming into the contact is not a priori known, contact represents a nonlinear problem even when the continuum behaves as a linear elastic material. Two bodies are considered: B Il ) and B(2) , Fig. 1. We will denote as the contact surface rg> the part of the body such that all material points where contact may occur at any B(1)

time t are included. Using a standard notation in contact mechanics we will assign to each pair of contact surfaces involved in the problem as slave and master surfaces. In particular, let rg> be the

slave surface and r~) be the master surface. The condition which must be satisfied is that

any slave particle cannot not penetrate the master surface. Let x be the projection point of the current position of the slave node Xk onto current position ofthe master surface r~) ,defined as

(1)

where ex =1,2 and 3a (~l ,~2) are the tangent covariant base vectors at the point x. These

tangents are defined using following relationships:

_ axla2 =-2 (2) a,; ~1=t'.~2=p

The relation (2) can be written as:

3a =xA~1,~2) (3)

The definition of the projection point allows us to define the distance between any slave node and the master surface. The normal gap or the penetration g N for slave node k is

defined as the distance between current positions of this node to the master surface r~):

(4)

where n refers to the normal to the master face r~) at point x (Fig. 1). Normal to be

defined using tangent vectors at the point i

(5)

2

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Figure 1. Geometry oCtile 3D node-to-segment contact element

This gap (4) gives the non-penetration conditions as follows: gN = 0 perfect contact; gN > 0 no contact; gN < 0 penetration (6)

If the analyzed problem is frictionless, function (6) completely defmes the contact kinematics. However, if friction is modeled, tangential relative displacement must be introduced. In this case the sliding path of the node Xk over the contact surface r~) is described by total

tangential relative displacement as

gT = nlgTII dt = ~Italialldt= J~taiPaapdt (7) , , , in time interval from to to t.

The time derivatives of parameter ~a in equation (7) can be computed from the

relation (1), [8]. In the geometrically linear case we obtain the following result

(8)

(9)

where o",p =lia . iip is the metric tensor in point i of the master surface r~). From the

equations (7) and (9) we can deduce the relative tangential velocity at the contact point

(10)

3

which yields

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3. Constitutive equations for contact interface

A contact stress vector t with respect to the current contact interface rg) can be split into

a normal and tangential part.

(11)

where aa is contravariant base vector. The stress acts on both surfaces according to the

action-reaction principle: t(~l ,~2) = -t in the contact point x. The tangential stress Ira is

zero in the case of frictionless contact. In the case of contact there is condition t;. < 0 . If

there is not penetration between the bodies, then relations gN > 0 and t;. = 0 hold. This

leads to the statements

(12)

which are known as Kuhn-Tucker conditions. Using the penalty method for normal stress, constitutive equation can be formulated as

(13)

where EN is the normal penalty parameter.

In tangential direction there is difference between stick and slip. As long as no sliding between two bodies occurs, the tangential relative velocity is zero. Ifthe velocity is zero, also the tangential relative displacement (10) is zero. This state is called stick case with the following restriction:

(14)

F or stick a simple linear constitutive model can be used to describe the tangential stress.

(15)

where Er is the tangential penalty parameter.

A relative movement between two bodies occurs if the static friction resistance is overcome and the loading is large enough such that the sliding process can be kept. The tangential stress vector is restricted as follows:

(16)

where II is friction coefficient. In the simplest form of Coulomb's law (16), II is constant

so there is no difference between static and sliding friction. After the introduction of the stick and slip constraints, we need to introduce indicator to define whether stick or slip actually take place. Therefore an indicator function

(17)

4

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is evaluated, which respect the Coulomb's model for frictional interface law. In the

equation (17) the frrstterm is !!tT!!=JlraaaPlrp •

A backward Euler integration scheme and return mapping strategy are employed to integrate the friction equations (17). If a state of stick is assumed, the trial values of the tangential contact pressure vector ITa' and the indicator function I at load step n+1 can be

expressed in terms of their values at load step n as follows

(18)

/rial II trial II I I (19)hn+1 = tTn+l - JI INn+1

The return mapping is completed by

{t~'::~+l if IsO (20)ITa n+1 = It I trial

JI MJ+I 'Ta n+1 if/>O

with

(21)

For the both cases, the penalty method can be illustrated as a group of linear elastic springs that force the body back to the contact surface when overlapping or sliding occurs.

4. Adjustment ofthe load step

When too many nodes coming into contact simultaneously, it may cause solution difficulties. Ideally, one node at a time should come into contact. The basic idea is to adjust the load step according to the changes of contact conditions. The aim of the method is to limit the number of nodes coming into contact on a load step by using prediction-correction algorithm. Number ofnodes Nc which get in contact for every step are defmed by user. The

increase or the decrease ofthe load step is written:

(22)

where p is a multiplicative factor which must be determined. The factor is calculated so

that the number of nodes coming into contact on the corrected load step is limited to the given number Nc ' The scalar pi is calculated at the fITst Newton iteration of the time

t + M fOf a given node likely to come into contact. By considering all the nodes, p can be

calculated. Then, the load step is corrected by use of p factof. The calculation is then

taken again with this new load step Mcor and so the configuration at the time t +Mcar is evaluated. Now, we explain the determination of p factor. With the goal to simplify and

clearer describe determination of P factor, we suppose that reference face unchanged

between times I and t + M and that node remains in contact with the same face. New load

5

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step is detennined so that the considered node comes exactly into contact at time t + ill"", .

SO, AI""g~ =0 . For each node k, likely to come into contact, the factor fl is defined by

(23)

All the coeficients fJk are classified in an ascending order,

(24)

The aim ofthe proposed method is to limit the number ofnodes coming into contact to Nc •

So, the coefficient is obtained by the relation (24) is:

(25)

5. Algorithm for frictional contact

For solution a nonlinear eqUilibrium equation with inequality constraints (4) as a result of contact, we use a standard implicit method. In order to apply Newton's method for the solution system of eqUilibrium equation, a linearization of the contact contributions is necessary. In this paper, we do not state the linearization procedure for standard finite element formulation as well as the contact interface law for the normal and tangential part. It could be found in [7]. The tangent stiffhess matrix for the normal contact is

KN =&NNNT (26)

The symmetric tangent stiffness matrix for stick condition is

(27)

(20) where

0 ap

-HID -Hlap

N= -H2o Tp = -H2ap na --aPT-a p' (28)

-H3D -H3ap

-H4D -H4ap

The linearization of n;:~+1 gives (for details see [5])

(28)

6

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The tangent stiffness matrix for slip condition is

The second term, the tangent matrix is non-symmetric, due to the Coulomb's friction can be viewed as a non-associative constitutive equation. Algorithm of the automatic adjustment of load step for frictional contact algorithm using penalty method is shown in Table 1.

Table 1. Algorithm ofthe automatic adjustment ofload step for frictional contact algorithm usinf! the penalty method LOOP over all load step LOOP over all iterations

LOOP over all contact segment k

Determination of the penetration g~ IF ;=1 AND Icor=1 THEN

Determination of fJk

(check for contact (6» IF gN ~ 0 THEN (the first iteration) IF i=1 THEN

set all active nodes to state stick, tT.+1 (15), compute matrix K~ick

ELSE Compute trial state: t~7:~+1 (18) and f;;:t (19)

IF f;;~a: ~ 0 THEN

tTa n+1 = t;.:a~+l ,compute matrix K~ck (27) GO TO (a)

ELSE ITa n+l = .u ItNn+11 n~:"~+1 ,compute matrix Ki;p (29)

ENDIF ENDIF

ENDIF IF (i=1 AND Icor=l) GO TO (b)

ENDIF ~a) ENDLOOP (b) END LOOP

IF Icor=O THEN Correction ofload step I:1teor = fJl:1t

Update Icor=l Automatic restart with I:1t = Meor

ENDIF END LOOP

7

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6. Example

in this exampie banding of quarter of tube analysed. Internal tube radius is r = 100mm and thickness t =20mm, .elastic modul E =400MPa and Poasson's ratio v =0.25. Tube is modeled with 1313 4-node enhenced 2D elements - plain strain. Banding of the tube is conducted using rigid plate, Fig. 2a. Penalty parameter is eN =Ix109 • Solution is obtained

by 47 steps ofdisplacement increments equal to 1.6 mm, Fig. 2b.

til

..................................................l",.....I"

a)tbe model b) Total displacement field, deformed configurati(ln Figure 2. Modle cevi

The test is realised with automatic adjustement of the step in the case of contact. The data of this adjustement is Nc =2 . This example ilustrates the utility of the method when the load step proposed by the user is too small. Without adjustement, 47 steps are necessary to obtain the imposed load. With presented method, one can note a very strong increase ofthe load step and therefore number of stpes necessary reduced to 32. The Fig. 3 illustrates this phenomenon and emphasises a non-linear evolution ofload step.

I-without automatic adjustement -with automatic adjustment I

o 5 10 15 20 25 30 35 40 45 50

Number of load step Figure 3. Evolution of load step

8

~ 80 E .§. 70

i60 E ~ 50 '"i40 '6 30'0 :5 20 ;J

.a 10 g w O~~-.----r----,----.----.----.---~---,----~---.

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7. Conclusions

The automatic adjustment of ioad step for the numerical tretment of contact has been proposed in this paper. The load step is adjusted in order to limit the number of changes of contact status during each load step. The numerical example indicates a possibility of applying the developed method in the analysis offinite deformation problems.

Acknowledgement. Theoretical basis of contact analysis in sections 3-5, was being developed within the project of Ministry of Science and Technological Development ­Development ofsoftware for explicit nonlinear dynamic analysis TR12005.

References

[I} Vulovic S. (2008),Nwnerical solution ofcontact problems using penalty method, Ph.D. Thesis, Faculty of Mech. Eng. Univ. ofKragujevac, Kragujevac.

[2] Kojic M., R. Slavkovic, M. Zivkovic, N. Grujovic, The software packages PAK, Faculty ofMechanical Engineering ofKragujevac, Serbia and Montenegro.

[3] Grujovic N. (1996), Contact problem solution by fmite element methods, Ph.D. Thesis, Faculty ofMech. Eng. Univ. ofKragujevac, Kragujevac,.

[4] Kojic M., K. J. Bathe (2005), Inelastic Analysis of Solids and Structures, Springer, Berlin-Heidelberg. [5] Wriggers P. (2002), Computational Contact Mechanics, J. Wiley & Sons Ltd, West Sussex, England. [6) Chamoret D., Saillard P., Rassineux A., Bergheau J.-M. (2003), New smoothing procedures in contact

mechanics, Journal ofComputational andApplied Mathematics, pp. 1-10. {7] Chamoret D., Saillard P., Bergheau 1.-M. (2002), Automatic Adjustment of the load step for contact problems,

Fifth World Congress on Computational Mechanics, 7-12 July, Vienna, Austria.

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