Modellingof nonwoven materials Stepan V. Lomov, Amit Rawal - PowerPoint PPT Presentation

Modellingof nonwoven materials Stepan V. Lomov, Amit Rawal Department Metallurgy and Materials Engineering, KULeuven Downloaded from: http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm 1

N oWoT ex: S pecs Fibrous assembly: Fibre properties Fibrous components Non-woven fabric Fibrous components Length Fabric weight & thickness Waviness and curvature Fibre content Orientation Random realisation Random realisation Random realisation Bonding Random realisation Geometry & Visualisation Individual Contacts and links properties of the realisation and Mechanical properties Monte Carlo for the Permeability assembly Properties of composite Downloaded from: http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm 2

N oWoT ex: G U I Downloaded from: http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm 3

Input: F ibreproperties Downloaded from: http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm 4

F ibreproperties EASTLON SN-3250CM HC SL hygienic Material PES PES Linear density, tex 0.22 0.33 Density, g/cm3 1.38 1.38 Diameter (computed), mm 0.0142 0.0174 Friction coefficient (ASSUMED) 0.3 0.3 Young modulus, GPa 11 11 Poisson ratio 0.25 0.25 Tenacity, cN/dtex 3.4 3.7 MPa 469 511 Elongation, % 60 57 Length, mm 51 57 Proportion, wt% 50 50 Areal density, g/m2 27.6 Thickness, mm 0.5 Vf_total, % 4.0 Downloaded from: http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm 5

Input: F ibrelength Downloaded from: http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm 6

Input: F ibreorientation Downloaded from: http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm 7

Measurements of the fibre orientation p z 3 2 y � p p 3 1 p � 2 1 x f INT f � � � � i f f k ; � � � � i f n cos � � � i 1 � f f � � � � � � i int k ds , i 1... N � � � � � i � f n cos � � � � � i s � � Downloaded from: http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm 8

Input: F ibrewaviness s s � � � � � � � � r ( ) s A r sin n r sin n � � � � � � � � � � � � 1 1 1 2 2 2 L L � � � � � � Downloaded from: http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm 9

Material Downloaded from: http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm 10

C ontacts Total contacts: 1509; 693 contacts/mm3 [EASTLON SN-3250CM]x[EASTLON SN-3250CM]: 142; 65 contacts/mm3 [EASTLON SN-3250CM]x[HC SL hygienic]: 777; 357 contacts/mm3 [HC SL hygienic]x[HC SL hygienic]: 590; 271 contacts/mm3 Downloaded from: http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm 11

C ontact types Downloaded from: http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm 12

O rientation averaging of the fibre tension Machine Poisson Direction � F_fibre C A’ B’ l cos � � b f A B � ’ l f b l cos l � f f � A O l sin � f A 1 � � Downloaded from: http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm 13

E quations web stress per unit width [N/m] for the test direction � directional parameter: fiber length projection on the test direction . n m � f 1 T K cos ( ) ( , ) � � � � � � � � � � � � � � � � � � � a 1 i 1 i 1 i � i 1 f 1 � frequency of the orientation n m K � f 2 cos ( ) ( , ); � � � � � � � � � � � � � � � � � � � � a 2 i 2 i 2 i i i � i 1 f 2 � fibre stress component mass per fibre orientation fraction unit area angle fabric strain 1 / 2 � � f 2 2 2 2 � � f ( ) f cos ( 1 ) ( 1 ) sin 1 � � � � � � � � � � � � � f fibre strain fibre tension diagram Poisson ratio Downloaded from: http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm 14

Input: C omponents and areal density T17 T17 T28 Downloaded from: http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm 15

Input: F ibre orientation In-plane fibre 0.16 a a=17.72 0.14 Relative Frequency orientation: 0.12 b=18.99 approximated by normal 0.1 0.08 distribution � = 21º 0.06 0.04 0.02 0 -90 -70 -50 -30 -10 10 30 50 70 90 Fibre Orientation Angle ( o ) T17 K( � ) 0.12 b T17 T28 Relative Frequency 0.1 � 0.08 2.2 3.3 4.4 12 0.06 0 ° 1.26 1.22 1.33 1.31 0.04 0.02 22.5 ° 1.10 1.13 1.19 1.21 0 45 ° 0.78 0.83 0.88 0.93 -90 -70 -50 -30 -10 10 30 50 70 90 Fibre Orientation Angle ( o ) 67.5 ° 0.34 0.43 0.43 0.50 90 ° 0.15 0.044 0.08 0.0011 Downloaded from: http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm 16

Input: F ibre tension 7 2.2 dtex 6 3.3 dtex 5 4.4 dtex Stress (cN/tex) 12 dtex 4 3 2 1 0 0 2 4 6 8 10 12 Strain (%) Downloaded from: http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm 17

Input : P oisson ratio 6 0° Poisson’s Rat 22.5° 4 45° 67.5° 90° 2 0 0 1 2 3 4 5 6 7 8 T28 Longitudinal Strain (% ) 4 0° T17 3.5 22.5° Poisson’s Ratio 3 45° 2.5 67.5° 2 90° 1.5 1 0.5 0 0 1 2 3 4 5 6 7 8 Longitudinal Strain (%) Downloaded from: http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm 18

R esults: D iagrams 1 0.7 Experimental Experimental 0.6 0.8 Incl. Poisson’s Ratio Stress (N/mm) Stress (N/mm) Incl. Poisson’s Ratio 0.5 Excl. Poisson’s Ratio Excl. Poisson’s Ratio 0.6 0.4 0.3 0° 0.4 0.2 0.2 0.1 0 0 0 1 2 3 4 5 6 7 8 0 1 2 3 4 5 6 7 8 Strain (%) Strain (%) T17 T28 0.1 0.12 Experimental Experimental 0.08 Stress (N/mm 0.1 Incl. Poisson’s Ratio Stress (N/mm) Incl. Poisson’s Ratio Excl. Poisson’s Ratio 0.08 0.06 Excl. Poisson’s Ratio 0.06 0.04 0.04 0.02 0.02 0 0 0 1 2 3 4 5 6 7 8 0 1 2 3 4 5 6 7 8 67.5° Strain (%) Strain (%) Downloaded from: http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm 19

R esults: Modules 20 18 P Experimental odulus (M 16 14 Incl. Poisson’s Ratio 12 Excl. Poisson’s Ratio 10 Secant M 8 6 4 2 0 T28 0 22.5 45 67.5 90 30 ngle ( o ) Test A Secant Modulus (MPa) Experimental T17 25 Incl. Poisson’s Ratio 20 Excl. Poisson’s Ratio 15 10 5 0 0 22.5 45 67.5 90 Test Angle ( o ) Downloaded from: http://www.mtm.kuleuven.ac.be/Research/C2/poly/index.htm 20