X - JEC Composites
X - JEC Composites
X - JEC Composites
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A Preliminary Design Tool for <strong>Composites</strong><br />
Beam Structures : 3D-Beam II<br />
<strong>JEC</strong>, Paris<br />
March, 2011<br />
Sung K. Ha<br />
Hanyang University, Korea<br />
Stanford Composite Design Group<br />
1
Beam Type Structures of <strong>Composites</strong><br />
Wind Turbine Blades and Tower<br />
Wings<br />
Non Crimp Fabrics (NCF)<br />
HSCL Turbine<br />
Courtesy of Chomarat<br />
Sporting Goods<br />
Box beams<br />
2
3D Beam<br />
Analysis of Composite Strucutres Needs Ply-by-ply inputs such as<br />
thickness, ply orientation, and material properties.<br />
MS Excel based User-friendly FEA program for beam type structures.<br />
An accurate, yet easy-to-use tool , greatly simplifying data input<br />
procedures.<br />
<br />
<br />
<br />
<br />
<br />
<br />
Long Structures (compared to cross-section)<br />
Any cross-sections<br />
Tapered / Untapered beam structure<br />
Loads (3 forces / 3 moments) at any location<br />
Multiply connected frames<br />
Modal analysis<br />
3
FEM formulation for a composite beam: 3D-Beam<br />
At each node (6 dof)<br />
d , <br />
3 3<br />
1) Displacement<br />
u ( x, y, z)<br />
d x<br />
x<br />
1 1 3 2 2 3<br />
d<br />
,<br />
<br />
1 1<br />
d<br />
,<br />
<br />
2 2<br />
<br />
u ( x, y, z)<br />
d x<br />
2 2 3 1<br />
u ( x, y, z)<br />
d x<br />
3 3 2 1<br />
2) strain-displacement<br />
d1<br />
<br />
2<br />
<br />
3<br />
u<br />
,<br />
x3<br />
x2<br />
22<br />
u 2, 2<br />
0 33<br />
u 3,<br />
3<br />
0<br />
x x x<br />
11 1 1<br />
1<br />
1<br />
1<br />
n 3 '<br />
n 3<br />
<br />
n2 =n 2 '<br />
n<br />
n 1 '<br />
3 '<br />
n 3 ''<br />
<br />
n 1<br />
n 1 '=n 1 ''<br />
d1 C1 0 S1 D1<br />
<br />
d<br />
<br />
2<br />
S1S2 C2 CS<br />
<br />
<br />
<br />
1 2D2<br />
d SC S CC D<br />
<br />
3 1 2 2 1 2 3<br />
n 2 ''<br />
n 2 '<br />
<br />
<br />
1<br />
1 d2<br />
<br />
1<br />
( u<br />
,<br />
u<br />
,<br />
) <br />
x3<br />
<br />
2<br />
2 x1<br />
x1<br />
<br />
1<br />
1 d3<br />
<br />
1<br />
( u<br />
,<br />
u<br />
,<br />
) <br />
x2<br />
<br />
2<br />
2 x x <br />
12 12 21 3<br />
13 1 3 3 1 2<br />
1<br />
1<br />
<br />
23<br />
( u2, 3<br />
u3,<br />
2<br />
) 1<br />
<br />
1 0<br />
2<br />
2<br />
<br />
x<br />
x<br />
<br />
1 11 1 3 2 2 3<br />
<br />
2 x<br />
<br />
5 13 5 2 1<br />
<br />
2 x<br />
<br />
6 12 6 3 1<br />
1<br />
1<br />
4
FEM formulation for a composite beam<br />
3) Constitutive equation (stress-strain)<br />
<br />
1<br />
<br />
<br />
5<br />
<br />
<br />
<br />
6<br />
C C C<br />
<br />
<br />
<br />
C C C<br />
<br />
C C C<br />
11 15 16<br />
15 55 56<br />
<br />
<br />
<br />
<br />
<br />
1<br />
<br />
<br />
5<br />
<br />
<br />
<br />
6<br />
local 16 56 66 local local<br />
C<br />
Local<br />
<br />
1<br />
<br />
<br />
5<br />
<br />
<br />
<br />
6<br />
<br />
1 C C C x C x C x C x C<br />
<br />
<br />
5 <br />
<br />
<br />
C C C x C x C x C x C<br />
<br />
<br />
<br />
6 <br />
C C C x C x C x C x C<br />
local<br />
11 16 15 2 15 3 16 3 11 2 11<br />
15 56 55 2 55 3 56 3 15 2 15<br />
16 66 56 2 56 3 66 3 16 2 16<br />
Resultants Loads vs strains<br />
<br />
<br />
<br />
1<br />
<br />
<br />
6<br />
<br />
<br />
<br />
<br />
5 <br />
<br />
D'<br />
<br />
1<br />
<br />
<br />
<br />
<br />
2<br />
<br />
<br />
3 <br />
4) F.E. formulation<br />
<br />
T<br />
d <br />
<br />
<br />
<br />
1 <br />
<br />
<br />
1<br />
<br />
5<br />
<br />
6<br />
<br />
5<br />
d MD' d<br />
<br />
<br />
6 <br />
<br />
<br />
h<br />
h<br />
d N d , N ( i 1, 2,<br />
3)<br />
i<br />
2<br />
<br />
a1<br />
a ai i<br />
2<br />
<br />
a1<br />
a<br />
ai<br />
Laminates<br />
F<br />
A G G B B B <br />
<br />
<br />
1 11 16 15 11 12 13 1<br />
<br />
G<br />
2 66<br />
G56 B21 B22 B<br />
<br />
F<br />
<br />
23<br />
<br />
6 <br />
F<br />
G<br />
3 55<br />
B31 B32 B<br />
<br />
<br />
<br />
33 <br />
5 <br />
<br />
<br />
M<br />
D<br />
1 <br />
11<br />
D12 D13<br />
1<br />
<br />
M<br />
sym.<br />
D D <br />
<br />
2 22 23 2<br />
<br />
<br />
M<br />
D<br />
3 <br />
33 <br />
3<br />
M 3<br />
eg . ., A11 = C11dxdx<br />
2 3<br />
F 3<br />
M 1<br />
F 1<br />
F2<br />
M<br />
2<br />
e<br />
2<br />
T T<br />
k B DBdx<br />
B DB jd<br />
e ( ) ( )<br />
<br />
<br />
x<br />
x<br />
1<br />
e<br />
e<br />
2<br />
x<br />
e<br />
1<br />
1<br />
<br />
1<br />
f e<br />
N f dx<br />
N( ) f jd<br />
x<br />
<br />
e<br />
2<br />
x<br />
e<br />
1<br />
<br />
1<br />
1<br />
m e<br />
N m dx<br />
N( ) m jd<br />
x<br />
<br />
1<br />
1<br />
e e e e e<br />
m d<br />
+k d f MD+KD<br />
<br />
F<br />
5
FEM formulation for a composite beam<br />
Laminates<br />
x 1<br />
d<br />
,<br />
<br />
1 1<br />
d<br />
,<br />
<br />
3 3<br />
d<br />
,<br />
<br />
2 2<br />
M 3<br />
Q 3<br />
N 1<br />
M 1<br />
Q2<br />
M<br />
2<br />
5) strain-displacement<br />
6) Constitutive equation<br />
(macro strain macro stress)<br />
7) Failure criterion : Quadratic Tsai-Wu criterion<br />
SMM+<br />
MMF<br />
•Failure<br />
•Fatigue Life<br />
a F , b F<br />
( i 1, 2, 6)<br />
aR<br />
2<br />
ij i j i i<br />
bR 1 0 R <br />
<br />
<br />
<br />
0 :safe<br />
0 :fail<br />
Strength ratio<br />
1 0 :fail<br />
k <br />
R 0 :safe<br />
6
Coordinate systems and Layup direction<br />
Z<br />
Global<br />
Y<br />
Element<br />
X₃<br />
X₂<br />
Fiber direction<br />
Ply<br />
X 1<br />
X<br />
X₁ (S)<br />
, ply angle<br />
Cross Section<br />
<br />
Global coordinates (X-Y-Z)<br />
Element coordinates (X 1 -X 2 -X 3 )<br />
Local coordinates (x 1 -x 2 -x 3 )<br />
Layup Sequence<br />
Direction, t<br />
t<br />
n<br />
S<br />
n1<br />
n2<br />
L#<br />
n3<br />
Laminates<br />
Bricks<br />
x 3<br />
<br />
t sn<br />
X 3<br />
Plies<br />
x 2<br />
<br />
X 2<br />
7
Program Flow : 3D Beam<br />
Input<br />
• Cross Section<br />
• Material property<br />
• Nodes (Global coordinates)<br />
•Elements (node connectivity)<br />
• Boundary conditions<br />
• Global Forces<br />
Main Analysis Modules<br />
Step 1 : Section & Material<br />
Step 2 : Global Geometry<br />
Step 3 : Loads<br />
Step 4 : Solve<br />
Output<br />
• Displacement & Rotation<br />
• Global Strains & Curvatures<br />
• Global Loadings & Moments<br />
• In-Plane Strains<br />
• In-Plane Loads<br />
• Strength Ratios<br />
• Mode shape & Natural<br />
Frequency<br />
•Ply Stresses & Strains<br />
3D Graphical Post Processor:<br />
iPost.exe<br />
8
3D Beam– Main Sheet<br />
3D BEAM “Main” sheet<br />
2010-07-30<br />
9
Step 1 : Specification of Material Properties<br />
Material DB sheet<br />
10
Step 1 : Sections: Coordinates, Plies, and Laminates<br />
[A] n ,[B] n ,[D] n<br />
[A] k ,[B] k ,[D] k<br />
[A] 2 ,[B] 2 ,[D] 2<br />
L1<br />
L2<br />
(x2,x3)<br />
<br />
L3<br />
<br />
[A] 1 ,[B] 1 ,[D] 1<br />
Laminates bricks<br />
x 3<br />
<br />
X 3<br />
plies<br />
x 2<br />
<br />
X 2<br />
Laminate brick nodes<br />
nodes<br />
11
Step 1 : Sections: Coordinates, Plies, and Laminates<br />
3D BEAM “Section DB” sheet<br />
(4)<br />
[A] n ,[B] n ,[D] n<br />
[A] k ,[B] k ,[D] k<br />
[A] 2 ,[B] 2 ,[D] 2<br />
[A] 1 ,[B] 1 ,[D] 1<br />
L2<br />
<br />
L3<br />
(4)<br />
(3)<br />
(2)<br />
(3)<br />
L1<br />
(x2,x3)<br />
<br />
Material DB sheet<br />
• SI unit<br />
(1)<br />
Ply group number<br />
p8<br />
…<br />
p1<br />
(2)<br />
Laminates<br />
bricks<br />
x 3<br />
<br />
X 3<br />
plies<br />
x 2<br />
•English unit<br />
<br />
X 2<br />
brick nodes<br />
Laminate nodes<br />
12
e.g., A rectangular thin-wall cross section<br />
a2<br />
n<br />
a1<br />
t<br />
a2<br />
2<br />
Direction of ply sequence<br />
[0 3 /45/-45/90 2 ] s<br />
a1<br />
(-2 , 1)<br />
(2 , 1)<br />
a2<br />
x 3<br />
x 2<br />
a1<br />
x1<br />
x 3<br />
x 2<br />
t<br />
1<br />
2"<br />
3<br />
4<br />
(-2 , -1)<br />
(2 , -1)<br />
x1<br />
4"<br />
Laminate #1<br />
Laminate #2<br />
a1<br />
a2<br />
Laminate #3<br />
Laminate #4<br />
Base Line Option :0<br />
13
Step 2 : Global Geometry (nodes and elements)<br />
3D BEAM “Global geometry sheet”<br />
[A] n ,[B] n ,[D] n<br />
[A] k ,[B] k ,[D] k<br />
[A] 2 ,[B] 2 ,[D] 2<br />
[A] 1 ,[B] 1 ,[D] 1<br />
14
3D BEAM “Loads sheet”<br />
Step 3 : Loads: forces and moments<br />
[A] n<br />
,[B] n<br />
,[D] n<br />
[A] k<br />
,[B] k<br />
,[D] k<br />
[A] 2<br />
,[B] 2<br />
,[D] 2<br />
Displacements & Rotations<br />
<br />
U 3<br />
[A] 1<br />
,[B] 1<br />
,[D] 1<br />
Z<br />
Y<br />
U 2<br />
<br />
X U 1 <br />
Forces & Moments<br />
M 3<br />
F 3<br />
M 2<br />
Z<br />
Y<br />
F 2<br />
X F 1 M 1<br />
<br />
Global coordinates (X-Y-Z)<br />
15
Step 4 : Results: Deflections, in-plane loads, etc.<br />
Y<br />
X<br />
0.5m<br />
1kN<br />
0.03m<br />
•Displacements &<br />
•Forces<br />
•Moments<br />
<br />
M<br />
• Rotations<br />
3<br />
U 3<br />
F 3<br />
Z<br />
<br />
Z<br />
M 2<br />
U 2<br />
F<br />
Y<br />
2<br />
Y<br />
X U 1 <br />
X F 1 M 1<br />
Cross-section:<br />
20 segments (laminates)<br />
‣ resultant forces<br />
0.005<br />
0<br />
‐0.005<br />
‐0.01<br />
‐0.015<br />
‐0.02<br />
‐0.025<br />
‐0.03<br />
Deflection along the X‐axis<br />
0 0.1 0.2 0.3 0.4 0.5 0.6<br />
U₁<br />
U₂<br />
U₃
Step 4 : Results: failure index, in-plane loads, etc.<br />
3D BEAM “Results sheet”<br />
at each section<br />
Cross‐section<br />
0.02<br />
[A] n ,[B] n ,[D] n<br />
[A] k ,[B] k ,[D] k<br />
[A] 2 ,[B] 2 ,[D] 2<br />
N 1<br />
N 2<br />
N 6<br />
0.015<br />
0.01<br />
[A] 1 ,[B] 1 ,[D] 1<br />
0.005<br />
0<br />
‐0.02 ‐0.015 ‐0.01 ‐0.005 0 0.005 0.01 0.015 0.02<br />
‐0.005<br />
z_b<br />
zT<br />
zB<br />
‐0.01<br />
‐0.015<br />
‐0.02<br />
At each section, in-plan loads, strains and strength ratios<br />
0.8<br />
0.6<br />
0.4<br />
0.2<br />
0<br />
‐0.2<br />
‐0.4<br />
‐0.6<br />
‐0.8<br />
In Plane stress at Element # 1<br />
N1<br />
N2<br />
N6<br />
0 5 10 15 20 25<br />
Laminate #<br />
0.006<br />
0.004<br />
0.002<br />
0<br />
‐0.002<br />
‐0.004<br />
‐0.006<br />
In Plane strain at Element # 1<br />
e1<br />
e2<br />
e6<br />
0 5 10 15 20 25<br />
Laminate #<br />
17<br />
16<br />
15<br />
Laminat #<br />
18<br />
14<br />
19<br />
13<br />
201.2<br />
1<br />
0.8<br />
0.6<br />
0.4<br />
0.2<br />
0<br />
‣Strength 12 ratio<br />
1<br />
11<br />
2<br />
10<br />
3<br />
9<br />
Failure Index (1/R)<br />
4<br />
5<br />
6<br />
7<br />
8<br />
17
Installation : 3D-beam and iPost (Graphic Post Processor)<br />
1 – Copy and Paste the 3D-beam and iPost into your folder.<br />
2. If needed, Install JRE (Java Runtime Environment) on your system to run JAVA Post<br />
Processor. You can download JRE from http://java.sun.com/javase/downloads/index.jsp<br />
This application is available for all operating systems.<br />
3 – Be sure to place “iPost.exe” file at same location as the 3D Beam II.xlsm software.<br />
Figure : 3D-beam & iPost<br />
18
iPost – Overview<br />
Post Process File Selection<br />
Parameter Setting<br />
Display Setting<br />
Graphics Area<br />
Field Output:<br />
Contour Values<br />
Note!!<br />
Current generated Post Process file will be automatically called.<br />
19
iPost– Parameter Setting<br />
Parameter Setting<br />
Scale Factor: 0.1 Scale Factor: 1<br />
Field Outputs:<br />
Nstress: stress from node<br />
Disp: displacement distribution<br />
Mode: mode shape<br />
Mat Number:<br />
All: elements with all mat<br />
1: elements with mat 1<br />
2: elements with mat 2<br />
& so on…<br />
Scale Factor:<br />
Any value<br />
20
iPost– Display Setting<br />
Display Setting<br />
On<br />
Off<br />
Window:<br />
1, 2, 4<br />
Wire Fram:<br />
On/Off<br />
Deformed<br />
Deformed & Undeformed<br />
Background:<br />
White/Black<br />
Deformed/Undeformed<br />
21
Comparison between 3D Beam and<br />
commecial FEA tools<br />
22
Case : Hollow Composite Beam with Circular Cross-section<br />
Deformation under simple loading<br />
Vertical<br />
100 N<br />
Torsion<br />
100 N · m<br />
D = 0.1 m<br />
L = 1 m<br />
[0/±45/90] S<br />
1.2<br />
Deflection<br />
Deformation normalized by Abaqus result<br />
1<br />
0.8<br />
0.6<br />
0.4<br />
0.2<br />
3D Beam II<br />
Abaqus<br />
0<br />
Deflection<br />
Rotational Angle<br />
Rotational Angle<br />
23
Case : Hollow Composite Beam with Circular Cross-section<br />
Natural frequencies & mode shapes<br />
D = 0.1 m<br />
L = 1 m<br />
[0/±45/90] S<br />
Mode 1<br />
Mode 2<br />
Natural Frequency (Hz)<br />
1800<br />
1600<br />
1400<br />
1200<br />
1000<br />
800<br />
600<br />
400<br />
3D Beam II<br />
Abaqus<br />
Mode 3<br />
200<br />
0<br />
Mode 1 Mode 2 Mode 3 Mode 4<br />
Mode 4<br />
24
Case : Hollow Composite Beam with Square Cross-section<br />
Results<br />
L = 1 m<br />
Load Case 1 Load Case 2<br />
100 N 100 N · m<br />
Load Case 1 : Max. Displacement<br />
Dispalcement (m)<br />
1.60E‐04<br />
1.40E‐04<br />
1.20E‐04<br />
1.00E‐04<br />
8.00E‐05<br />
6.00E‐05<br />
4.00E‐05<br />
2.00E‐05<br />
0.00E+00<br />
Abaqus (Shell Element)<br />
A<br />
3D Beam II5.50<br />
Load Case 2 : Max. Rotation<br />
Rotation (radians)<br />
8.00E‐04<br />
7.00E‐04<br />
6.00E‐04<br />
5.00E‐04<br />
4.00E‐04<br />
3.00E‐04<br />
2.00E‐04<br />
1.00E‐04<br />
0.00E+00<br />
Abaqus (Shell Element)<br />
3D Beam II5.50<br />
H = 0.1m<br />
H = 0.1m<br />
W = 0.1m<br />
W = 0.1m<br />
Laminate Layup : [0 8 /±45 8 /90 8 ] S<br />
Material : AS/H3501<br />
Abaqus<br />
(Shell Element)<br />
3D Beam II5.50<br />
Load Case 1<br />
Load Case 2
Case : Hollow Composite Beam with Square Cross-section<br />
Results : Natural Frequencies & Mode shapes<br />
Abaqus<br />
(Shell Element)<br />
Abaqus<br />
(Beam Element)<br />
3D Beam II5.50<br />
L = 1 m<br />
Laminate Layup : [0 8 /±45 8 /90 8 ] S<br />
Material : AS/H3501<br />
Mode 1<br />
130.45 120.32 132.64<br />
Frequency (Hz)<br />
1800<br />
1600<br />
1400<br />
1200<br />
1000<br />
800<br />
600<br />
Abaqus (Shell Element)<br />
Abaqus (Beam Element)<br />
3D Beam II5.50<br />
Mode 2<br />
705.49 972.93 743<br />
400<br />
200<br />
0<br />
1st Mode 2nd Mode 3rd Mode 4th Mode<br />
Mode 3<br />
792.25 791.77 923.59<br />
Mode 4<br />
1539.5 1648.8 1481.6
Case :Ellipse Composite Beam<br />
Results<br />
D = 0.1 m<br />
L = 1 m<br />
Load Case 1 Load Case 2<br />
100 N<br />
100 N · m<br />
Load Case 1 : Max. Displacement<br />
Dispalcement (m)<br />
8.00E‐03<br />
7.00E‐03<br />
6.00E‐03<br />
5.00E‐03<br />
4.00E‐03<br />
3.00E‐03<br />
2.00E‐03<br />
1.00E‐03<br />
0.00E+00<br />
Abaqus (Shell Element) Abaqus (Beam Element) 3D Beam II5.50<br />
Load Case 2 : Max. Rotation<br />
Rotation (radians)<br />
2.50E‐02<br />
2.00E‐02<br />
1.50E‐02<br />
1.00E‐02<br />
5.00E‐03<br />
0.00E+00<br />
Abaqus (Shell Element)<br />
Abaqus (Beam<br />
Element)<br />
3D Beam II5.50<br />
5 cm<br />
5 cm<br />
10 cm<br />
Laminate Layup : [0/±45/90] S<br />
Material : AS/H3501<br />
10 cm<br />
Abaqus<br />
(Shell Element)<br />
Abaqus<br />
(Beam Element)<br />
3D Beam II5.50<br />
Load Case 1<br />
Load Case 2
Case :Ellipse Composite Beam<br />
Results : Natural Frequencies & Mode shapes<br />
D = 0.1 m<br />
Abaqus<br />
(Shell Element)<br />
Abaqus<br />
(Beam Element)<br />
3D Beam II5.50<br />
L = 1 m<br />
61.46 61.61 61.93<br />
Laminate Layup : [0/±45/90] S<br />
Material : AS/H3501<br />
Mode 1<br />
Frequency (Hz)<br />
700<br />
600<br />
500<br />
400<br />
300<br />
200<br />
100<br />
Abaqus (Shell Element)<br />
Abaqus (Beam Element)<br />
3D Beam II5.50<br />
Mode 2<br />
Mode 3<br />
103.88 101.95 104.93<br />
366.15 379.43 371.56<br />
0<br />
1st Mode 2nd Mode 3rd Mode 4th Mode<br />
Mode 4<br />
613.01 610.32 620.27
Parametric study using 3D Beam<br />
29
.<br />
Parametric Study-Easy to change the layup angles<br />
3D BEAM “Section DB” sheet<br />
Plies<br />
Laminates<br />
Change ply angle for 3 cases<br />
θ<br />
Case (1) 30°<br />
Case (2) 45°<br />
Case (3) 60°<br />
•[0/±θ/90]s<br />
30
Results: a clamped beam with circular cross-section<br />
Y<br />
Z<br />
Displacement U3<br />
Z<br />
X<br />
X<br />
Case (1) : θ = 30° ; Deflection= -0.014 m<br />
Case (2) : θ = 45° ; Deflection= -0.018 m<br />
Case (3) : θ = 60° ; Deflection= -0.020 m<br />
31
Results: a clamped beam with circular cross-section<br />
A cantilever beam<br />
under concentrated<br />
tip load<br />
Results at the root<br />
In plane load<br />
BOTTOM<br />
Fixed<br />
TOP<br />
L9<br />
L10<br />
L11<br />
L8<br />
Y<br />
L7<br />
L6 L5<br />
L4<br />
L3<br />
TOP<br />
Z<br />
L2<br />
(Global Z coordinate)<br />
L1<br />
Y<br />
L20<br />
In plane strain<br />
BOTTOM<br />
L12<br />
L13<br />
L14<br />
BOTTOM<br />
L15 L16<br />
L17<br />
X<br />
L18<br />
L19<br />
TOP<br />
- In plane load & strain are same for<br />
case(1),(2) and (3).<br />
32
Effect of fiber angles on stress distribution: Circular Beam<br />
At root<br />
Fixed<br />
L8<br />
L7<br />
L6<br />
TOP<br />
L5<br />
L4<br />
L3<br />
L9<br />
L10<br />
Z<br />
(Global Z coordinate)<br />
L2<br />
L1<br />
L11<br />
Y<br />
Y<br />
L20<br />
L12<br />
L13<br />
L14<br />
BOTTOM<br />
L15<br />
L16<br />
L17<br />
X<br />
L18<br />
L19<br />
Laminate #<br />
Tension<br />
Compression<br />
Small fiber angle reduces strength ratios<br />
θ<br />
Fiber<br />
33
Effect of ply angles on natural frequencies : Circular Beam<br />
Natural frequencies & modal shapes<br />
1 st Mode shape<br />
2 nd Mode shape<br />
3 rd Mode shape<br />
Case(1)<br />
: 30°<br />
Case(2)<br />
: 45°<br />
Case(3)<br />
: 60°<br />
34
Analysis of a Bend-Twisting Coupled<br />
Box Beam<br />
35
Tension-Shear Coupling in a laminate<br />
A tension-shear coupling term,<br />
A 16<br />
Balanced<br />
x 2<br />
x 1<br />
A16 0<br />
6 0<br />
N 1<br />
1<br />
1 A11 A12 0 N1<br />
<br />
<br />
A A 0 N<br />
2 21 22 2<br />
<br />
<br />
6<br />
0 0 A <br />
66<br />
N <br />
<br />
<br />
<br />
6<br />
<br />
<br />
Unbalanced<br />
x 2<br />
x 1<br />
A16 0<br />
<br />
6<br />
0<br />
N 1<br />
1<br />
1 A11 A12 A <br />
16 N1<br />
<br />
<br />
A A A N<br />
2 21 22 26<br />
2<br />
<br />
<br />
6<br />
A61 A62<br />
A <br />
66<br />
N <br />
<br />
<br />
<br />
6
Bend-Twist Coupling<br />
M<br />
EI<br />
C 2<br />
<br />
T<br />
<br />
C GJ<br />
<br />
1<br />
<br />
[0 / ] 100<br />
A<br />
16<br />
0<br />
If isotropic or balanced,<br />
For unbalanced, C 0<br />
C 0<br />
Twist<br />
Bend<br />
[0 / ] 100<br />
A<br />
16<br />
0<br />
37
A composite bend/twist coupled box beam.<br />
A bend/twist coulpled box-beam.<br />
Tip<br />
y<br />
x<br />
z<br />
<br />
Z<br />
ply thickness: 0.1 mm<br />
composite material : IM6/ep<br />
[ 45 80]<br />
[0 / ] 100<br />
[0 / ] 100<br />
bidirectional upper NCF:<br />
bidirectional lower NCF:<br />
length:10 m<br />
height:0.5 m<br />
width:0.5 m<br />
[0 / ] m<br />
[0 / ] m
Bend/twist coupling using birectional NCF<br />
Analysis tool : 3D-beam<br />
4<br />
L#3<br />
3<br />
0.24<br />
0.14<br />
0.04<br />
L#4<br />
‐0.252 ‐0.152 ‐0.052 0.048 0.148 0.248<br />
Base line<br />
Top line<br />
Bottom line<br />
[0 / ] m<br />
‐0.06<br />
L#2<br />
‐0.16<br />
[ 45] n<br />
[0 / ] m<br />
[ 45] n<br />
L#1<br />
‐0.26<br />
1 2
Bend/twist coupling using birectional NCF<br />
Analysis tool : 3D-beam<br />
twist/bend coupling,<br />
Z<br />
<br />
d<br />
d <br />
twisting angle, deg<br />
bending angle, deg<br />
Bidirectional NCF can be used to cause an intrinsically bend/twist coupling.<br />
0.25<br />
0.2<br />
bending angle, deg<br />
0.5<br />
0<br />
Z<br />
<br />
d<br />
d <br />
[ 45] n<br />
[0 / ] m<br />
[0 / ] m<br />
[ 45] n<br />
0.15<br />
0.1<br />
0.05<br />
0<br />
twisting angle, deg<br />
0 15 30 45 60 75 90<br />
-0.5<br />
-1<br />
-1.5<br />
-2<br />
twist/bend coupling<br />
outer ply angle, , deg
Zero displacement using Bend-Twist coupling<br />
Deflection, m<br />
Rotation, deg<br />
[ 4580]<br />
[0100 / 100]<br />
[ 45 ]<br />
80<br />
[0100 / 100]<br />
Top : [0 / 45 ]<br />
100 100<br />
Bottom : [0 / 45 ]<br />
100 100<br />
, deg<br />
Bending + Torsion<br />
No deflection<br />
Bending force only<br />
P<br />
+ <br />
P 0.78N<br />
0.78N<br />
Torsion only T 1 Nm T 1 Nm
Application to Braided Composite Beams<br />
42
Beam Type Composite Applications: Braided composites<br />
<br />
Braided <strong>Composites</strong><br />
Airbeams, framing<br />
aircraft maintenance hangars <br />
Composite Bridge Arches<br />
<br />
High Tech Hockey Stick<br />
<br />
Baseball composites bats<br />
by courtesy of A&P Technology<br />
43
Braided structure with varying cross-sections<br />
30°<br />
2θ<br />
<br />
45°<br />
60°<br />
length<br />
width<br />
44<br />
2011,03,021
Variation of Material Properties with Braid angle<br />
45
Baided Beam with Varying Cross-sections<br />
[ / <br />
] m<br />
46
Application to Design of Wind Turbine<br />
Blades<br />
HSCL Turbine<br />
47
Application: 5 kW Wind turbine blades<br />
• Rated Power: 5 kW<br />
• Rated wind speed: 10 m/s<br />
• Hub height: 10 m<br />
• Rotor diameters: 2.5 m<br />
• Cut in wind speed: 4 m/s<br />
• Cut out wind speed: 25 m/s<br />
• Annual mean wind speed: 5 m/s<br />
• Average Reynolds # : 1.5 x 10 6<br />
• Vertical Wind Shear: α = 0.2<br />
• Weibull Distribution: k = 2<br />
• Blades = 3<br />
• Orientation = Upwind<br />
• Rotation = Clockwise<br />
• Speed = Variable<br />
• Control = Pitch regulated<br />
*Reference: Finite element analysis with an improved failure criterion<br />
for composite wind turbine blades, Forsch Ingenieurwes (2008) 72: 193–207<br />
Hub<br />
D<br />
Hub height<br />
Airfoil NACA 4412<br />
Rotor Radius = 2.5 m<br />
Sections = 12<br />
Twist = 18 o<br />
Neck<br />
0º<br />
Material:<br />
Hub Metal and Composite*<br />
Neck Composite*<br />
Shell Composite*<br />
Fig: Model of a wind turbine blade<br />
* E-glass LY556 epoxy resin lamina Twist<br />
angle<br />
Shell<br />
18º<br />
0º
Application: Wind turbine blades<br />
Distributed loads : Fz/length= 350N/ (2.5 m)<br />
[ Al(4mm)/0 8 / (±45) 4 ]<br />
[ 0 8 / (±45) 4 ]<br />
2.5m<br />
[ 0 6 / (±45) 2 ]<br />
Layup sequence<br />
Material : E-glass LY556<br />
Wing sections<br />
Airfoil NACA 4412<br />
Twist = 18 o<br />
0.08<br />
0.06<br />
0.04<br />
0.02<br />
0<br />
‐0.02 0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16<br />
‐0.02<br />
‐0.04<br />
‐0.06<br />
‐0.08
Application : Wind turbine blade<br />
50
Application : Wind turbine blade<br />
Element #1<br />
In Plane stress at Element # 1<br />
0.03<br />
N1<br />
0.02<br />
N2<br />
0.01<br />
N6<br />
0<br />
‐0.01<br />
0 5 10 15 20 25<br />
‐0.02<br />
‐0.03<br />
Laminate #<br />
Element #4<br />
In Plane stress at Element # 4<br />
0.04<br />
N1<br />
0.03<br />
N2<br />
0.02<br />
N6<br />
0.01<br />
0<br />
‐0.01 0 5 10 15 20 25<br />
(1)<br />
‐0.02<br />
‐0.03<br />
‐0.04<br />
Laminate #<br />
Element #8<br />
In Plane stress at Element # 8<br />
0.06<br />
N1<br />
0.04<br />
N2<br />
0.02<br />
N6<br />
0<br />
‐0.02<br />
0 5 10 15 20 25<br />
‐0.04<br />
‐0.06<br />
Laminate #<br />
In Plane strain at Element # 1<br />
0.00008<br />
0.00006<br />
0.00004<br />
0.00002<br />
e1<br />
e2<br />
e6<br />
0<br />
‐0.00002 0 5 10 15 20 25<br />
‐0.00004<br />
‐0.00006<br />
‐0.00008<br />
Laminate #<br />
(8)<br />
In Plane strain at Element # 4<br />
0.0006<br />
(4)<br />
0.0004<br />
0.0002<br />
e2<br />
e6<br />
0<br />
‐0.0002<br />
0 5 10 15 20 25<br />
‐0.0004<br />
‐0.0006<br />
Laminate #<br />
In Plane strain at Element # 8<br />
0.0015<br />
0.001<br />
e1<br />
e2<br />
0.0005<br />
e6<br />
0<br />
0 5 10 15 20 25<br />
‐0.0005<br />
‐0.001<br />
Laminate #<br />
e1<br />
19<br />
18<br />
17<br />
16<br />
15<br />
14<br />
13<br />
Laminat #<br />
19<br />
18<br />
17<br />
16<br />
15<br />
14<br />
13<br />
Laminat #<br />
19<br />
18<br />
17<br />
16<br />
15<br />
14<br />
13<br />
Laminat #<br />
1<br />
20 0.015<br />
0.01<br />
0.005<br />
0<br />
12<br />
11<br />
1<br />
200.1<br />
0.08<br />
0.06<br />
0.04<br />
0.02<br />
0<br />
12<br />
11<br />
1<br />
200.2<br />
0.15<br />
0.1<br />
0.05<br />
0<br />
12<br />
11<br />
2<br />
10<br />
2<br />
10<br />
2<br />
10<br />
Failure Index (1/R)<br />
3<br />
4<br />
5<br />
6<br />
7<br />
8<br />
9<br />
Failure Index (1/R)<br />
3<br />
4<br />
5<br />
6<br />
7<br />
8<br />
9<br />
Failure Index (1/R)<br />
3<br />
4<br />
5<br />
6<br />
7<br />
8<br />
9<br />
51
Effects of stiffeners thickness on wind turbine blades<br />
Stiffener T300/N5208 [0 n ]<br />
E-glass/LY556 Epoxy<br />
Leading edge<br />
Trailing edge<br />
Upper Spar Cap<br />
Lower Spar Cap<br />
[0/+45/0] 60 [0/+45/0] 40 [0/+45/0] 40 [0/+45/0] 10<br />
Shear web [0/+45/0] 8 [0/+45/0] 8 [0/+45/0] 8 [0/+45/0] 8<br />
Stiffener T300/N5208<br />
Case (1) : n = 0;<br />
Case(2) : n = 10;<br />
Case(3) : n = 20.<br />
52
Blade deflection : Ultimate load<br />
Ultimate load at the tip<br />
4,000 N/m<br />
Deflection<br />
: No Stiffener<br />
: Stiffener =[0 10 ]<br />
T300/N5208<br />
: Stiffener =[0 20 ]<br />
T300/N5208<br />
53
Strength ratio : Ultimate load<br />
(1) (2) (3)<br />
Strength ratio (Tsai-Wu)<br />
(1) (2) (3)<br />
Laminate #<br />
L8 L7 L6 L5<br />
L10 L9<br />
L4<br />
L3<br />
L11<br />
L25<br />
L2<br />
L1<br />
L12 L26<br />
L28<br />
L29<br />
L27<br />
L30<br />
L13<br />
L14 L15 L16 L17 L18 L19 L20 L21 L22 L23 L24<br />
54
Vibration mode<br />
: No Stiffener<br />
: Stiffener =[0 10 ] Graphite<br />
: Stiffener =[0 20 ] Graphite<br />
1 st mode shape<br />
1 st 2 nd 3 rd 4 th<br />
Vibration modes<br />
2 nd mode shape 3 rd mode shape 4 th mode shape<br />
55
Summary and Conclusion<br />
• The 3D-beam can be used as a preliminary design tool for compoiste structures.<br />
• It is based on a composite beam theory, yielding as accurate results as 3D modeling.<br />
• Yet easy-to-use tool.<br />
• Calculate displacements, strains, stresses, failure index and natural vibration modes.<br />
• Biaxial unbalanced laminates and beams,<br />
• Braided Composite Beams<br />
• A “3D Beam II5.55p” (public version) is available to the audience.<br />
Thank you for your attention !!!<br />
sungha@hanyang.ac.kr<br />
title: 3DBEAM<br />
56