Transcript Second Progress Report Slides.pptx

Analysis of Simply Supported Aluminum and
Composite Plates with Uniform Loading to
Determine Equivalent Plate Ply Stack-Up
Second Progress Report
10/28/2013
Thin Plate Theory
Three Assumptions for Thin Plate Theory
• There is no deformation in the middle plane of the
plate. This plane remains neutral during bending.
• Points of the plate lying initially on a normal-to-themiddle plane of the plate remain on the normal-tothe-middle surface of the plate after bending
• The normal stress in the direction transverse to the
plate can be disregarded
Material Properties of Composite Laminate
Edge Length (a)
24 inch
Ply Thickness
0.040 inch
E1
2.25e7 psi
E2
1.75e6 psi
E3
1.75e6 psi
ν12
0.248
ν23
0.458
ν13
0.248
G12
6.38e5 psi
G23
4.64e5 psi
G13
6.38e5 psi
Applied Surface
Pressure (q)
10 psi
Governing Equations
Analysis and Performance of Fiber Composites: Agarwal & Nroutman
Governing Equations (cont.)
Mechanics of Composite: Jones
ANSYS Model with Mesh
Side 1
Side 1
Side
Side4 4
Side
Side2 2
Origin
Origin
Side 3
Side 3
• Due to Symmetry only a quarter of the
plate needs to be modeled
• The mesh size has an edge length of
0.75”
•Side 1 and Side 2 are constrained against
translation in the z-direction.
•Side 2 and Side 3 is constrained against
rotating in the x-direction
•Side 1 and Side 4 is constrained against
rotation in the y-direction
•The origin is constrained against motion
in the x- and y-directions
• A pressure of 10 psi is applied to the
area
Results of Composite Plate
Composite Plate Results
[0 90 0 90]s Laminate
•From governing equations:
wmax = 0.7146”
• From ANSYS
wmax = 0.7182”
• % Error = -0.5%
Aluminum Plate Results
(ref. First Progress Report)
Aluminum Plate Results
•From governing equations:
wmax = 0.941399”
• From ANSYS
wmax = 0.941085”
• % Error = 0.033%
Results of Composite Plate (ANSYS)
Laminate Stack-up
Deflection (in)
[0 90]s
5.653
[0 90 0 90]s
0.7182
[0 90 0 90 0 90]s
0.2141
[0 90 0 90 0 90 0 90]s
0.091
[+/-30 0]s
1.404
[+/-45 0]s
1.271
[+/-60 0]s
1.405
[+/-30 0 +/-30 0]s
0.1592
[+/-45 0 +/-45 0]s
0.1452
[+/-60 0 +/-60 0]s
0.1600
[90 60 45 30 0]s
0.0014
[90 30 0]s
0.0014
[90 45 0]s
0.0036
[90 60 0]s
0.0044
Findings
• From Slide 8, most of the ply arrangements
that were created will perform better than the
0.25” thick aluminum plate.
• I will now continue the analysis of these plates
to determine if any of the laminates will fail
under this loading.
Upcoming Deadlines
• Work on Thin Plate Analysis for Composite
Plate for Laminate that aren’t cross-ply
• Failure Criterion Methods for Composite
Stack-up