Meso-F E analysis of textile composites: Solutions, challenges, problems Stepan V. LOMOV, Dmitry S. IVANOV, Ignaas VERPOEST Department MTM, Katholieke Universiteit Leuven Hiroaki NAKAI, Tetsusei KURASHIKI, Masaru ZAKO Department of Management of Industry and Technology, Osaka University 1 Downloaded from http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm
C ontents 1. Introduction: Road map for meso-FE modelling of textile composites 2. WiseTex/MeshTex/SACOM: specialised state-of-the-art FE package for textile composites 3. Boundary conditions: Periodic and not-that-periodic 4. Damage modelling: Paradoxes of stiffness degradation scheme and new damage mechanics approach 5. Conclusions 2 Downloaded from http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm
1. Introduction: Road map for meso-FE modelling of textile composites 2. WiseTex/MeshTex/SACOM: specialised state-of-the-art FE package for textile composites 3. Boundary conditions: Periodic and not-that-periodic 4. Damage modelling: Paradoxes of stiffness degradation scheme and new damage mechanics approach 5. Conclusions 3 Downloaded from http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm
A gallery stitched 3-axial braid plain weave Knitted SMA 3D woven NCF 4 Downloaded from http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm
Textile C omposite A rchive https://textilecomposite.tamu.edu/ Laboratoire de Mécanique des Contact et des Structures, LaMCoS, INSA Lyon School M3, University of Nottingham Department MTM, Katholieke Universiteit Leuven Texas A&M University Department of Management of Industry and Technology, Osaka University 5 Downloaded from http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm
meso-F E : R oad map Geometric modeller Geometry corrector Meshing Assign material N+2 N+1 N properties Boundary conditions FE solver, postprocessor Homogenisation Damage analysis 6 Downloaded from http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm
1. Introduction: Road map for meso-FE modelling of textile composites 2. WiseTex/MeshTex/SACOM: specialised state-of-the-art FE package for textile composites • Geometric preprocessor: WiseTex • Problem of interpenetration of the yarns and solution • MeshTex: specialised mesher and data assignment • SACOM solver and post-processing • Example: 3D woven fabric 3. Boundary conditions: Periodic and not-that-periodic 4. Damage modelling: Paradoxes of stiffness degradation scheme and new damage mechanics approach 5. Conclusions 7 Downloaded from http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm
WiseTex–MeshTex/S A C O M WiseTex, K.U. Leuven MeshTex, Osaka University 8 Downloaded from http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm
Interpenetration of yarn volumes Splitting Separation � z - � z Deformation 9 Downloaded from http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm
MeshTex: Meshing, woven fabrics imported WiseTex model mesh finesse, yarns added space total thickness between yarns corrected interpenetrations mesh finesse, matrix actual VF mesh quality 10 Downloaded from http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm
MeshTex: Material properties VF in the yarn, imported from WiseTex fibre data, imported from WiseTex Homogenised UD, Chamis matrix data 11 Downloaded from http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm
MeshTex: H omogenisation matrix data Stiffness matrix and engineering constants 12 Downloaded from http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm
MeshTex, Boundary conditions identical mesh on the corresponding faces 13 Downloaded from http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm
MeshTex: S tress analysis 14 Downloaded from http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm
D amage model (built-in in S A C O M) –1 Damage initiation: Hoffmann Definition of the damage mode Z 2 2 2 F C ( ) C ( ) C ( ) � � � � � � � � � � � � 1 T Z 2 Z L 3 L T T 2 2 2 C C C C C C L � � � � � � � � � � � � 4 5 6 7 8 9 L T Z TZ ZL LT 1 1 1 1 � � � C � � � � � � 1 t c t c t c � � 2 F F F F F F � T T Z Z L L � � � 1 1 1 1 � � � C � � � � � 2 t c t c t c � � 2 F F F F F F � � Z Z L L T T � � 1 1 1 1 � � � C � � � � � � 3 t c t c t c � � 2 F F F F F F � � L L T T Z Z � � 1 1 1 1 1 1 � C , C , C � � � � � � 4 5 6 t c t c t c F F F F F F � L L T T Z Z � 2 2 2 � 1 1 1 � � � � � � C , C , C � � � � � � � � � � 7 8 9 � s � � s � � s � F F F � � TZ � � ZL � � LT � � � 15 Downloaded from http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm
D amage model (built-in in S A C O M) –2 16 Downloaded from http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm
E xample: 3D woven fabric eps_X in collaboration with A.E. Bogdanovich, D. Mungalov (3Tex) 17 Downloaded from http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm
3D woven fabric –Tensile diagram 500 exp 450 MeshTex 0.1 400 MeshTex 0.01 350 300 sig, MPa 250 200 150 100 50 0 0 0.5 1 1.5 2 2.5 3 eps, % correct change of stiffness strength prediction depends on the assumed L-strength for UD 18 Downloaded from http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm
P redictions of the damage onset Experiment FE, strain 0.22% Damage starts at Z-yarn locations: • T-mode at the edges of fill • Z-mode in Z-yarns bundle-boundary cracks in Z-yarns FE, strain 0.30% transverse cracks in fill T-mode in fill 19 Downloaded from http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm
D eveloped damage Experiment: strain 0.5% FE warp Z warp fill 20 Downloaded from http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm
C onclusions: WiseTex–MeshTex/S A C O M State-of-the-art numerical W iseTex Geometric modeller tool for preparation of FE models and FE analysis of Geometry corrector textile composites on meso-structural level Meshing M esh Tex Assign material properties Boundary conditions FE solver, postprocessor SACOM , Homogenisation Visu a l SACO M Damage analysis 21 Downloaded from http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm
1. Introduction: Road map for meso-FE modelling of textile composites 2. WiseTex/MeshTex/SACOM: specialised state-of-the-art FE package for textile composites 3. Boundary conditions: Periodic and not-that-periodic • Periodic BC for symmetry-reduced unit cells • Periodic BC for non-orthogonal unit cell • Deviation from periodicity: stress-strain fields near free surface 4. Damage modelling: Paradoxes of stiffness degradation scheme and new damage mechanics approach 5. Conclusions 22 Downloaded from http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm
S ymmetry of a unit cell and reduction of size of the F E problem x � 1 -x � 2 coordinate plane coincides with the mid-plane of the braid 1 Unit cell 2 Half of the UC 3 Quarter of the UC Rotation around the Rotation around the x 3 axis by � x � 1 axis by � 23 Downloaded from http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm
P eriodic boundary conditions (translational symmetry) d 2 d 1 24 Downloaded from http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm
E quivalent co-ordinate systems 1 3 x x � � 1 0 0 1 1 � 2 � � x x � � � � 3 � � a 0 1 0 2 2 � � ij � � x x 0 0 1 � � � 3 3 � � x a x � i ij j 1 2 (j k) ( 1 ) – � � i n u n (j k) ( 2 ) = � j i d k u i (j k) - fixed indexes –point out the macro deformation (6 boundary value problem to solve) J.D.Witcomb et al. Derivation of boundary conditions…, J Compos Mat , 34 , 9, 2000, 724-747 25 Downloaded from http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm
BC : ¼of unit cell in-face, t thickness, z normal, n “A” u t (2) + u t (1) =0 u z (2) -– u z (1) =0 u n =0 u t (1=2 * ) = 0 “B” and “C” u t (2) – u t (1) =0 u z (2) + u z (1) =0 u n =0 u t (1=2 * ) = 0 u z (1=2) = 0 26 Downloaded from http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm
N on-orthogonal unit cell does not “forgive” errors in boundary conditions Dirichlet u( x ) � � = � � � x �� � x UD - hexagonal packing Dirichlet = periodic Periodic BC u( x ) � � - � = � � � x �� � x 27 Downloaded from http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm
D ifferent tricks Errors against the analytical solution,% 60 Layered composite Dirichlet Self-cons. 50 Embedding 40 30 20 Dirichlet 10 Embedding 0 Self-cons. C x x x x C x x y y Dirichlet C y y y y C x y x y C x y y y C x y x x Self-consistent Embedded 28 Downloaded from http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm
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