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Uses for Composite Materials. AircraftProsthetic LimbsAuto bodyAuto FrameBridge ReinforcementShafts and RodsBody Armour. Advantages of Composites. Density of aluminum alloy approximately 2800 kg/m3Density of carbon/epoxy approximately 1580 kg/m3Tensile strength of aluminum alloy 7075-T6 is 570 MPaTensile strength of carbon/epoxy 1830 MPa.
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1. Modeling of Composite Tubes Using ANSYS JEFF KAPKE
ME 450 Introduction to CAE
May 3, 2000
Submitted to: Professor H.U. Akay
2. Uses for Composite Materials Aircraft
Prosthetic Limbs
Auto body
Auto Frame
Bridge Reinforcement
Shafts and Rods
Body Armour
Composites weight less then their metallic equivalent.
Composites can be stronger than Composites weight less then their metallic equivalent.
Composites can be stronger than
3. Advantages of Composites Density of aluminum alloy approximately 2800 kg/m3
Density of carbon/epoxy approximately 1580 kg/m3
Tensile strength of aluminum alloy 7075-T6 is 570 MPa
Tensile strength of carbon/epoxy 1830 MPa This is about 44% less dense than aluminum.
The tensile strength is about 70% stronger.
The greatest disadvantage is the cost of composite materials compared to common metals.This is about 44% less dense than aluminum.
The tensile strength is about 70% stronger.
The greatest disadvantage is the cost of composite materials compared to common metals.
4. Isotropic Vs. Orthotropic
Iso – Properties are the same in all directions
Ortho – Properties are not the same in all directions.
- With Fiber Composites the fiber orientation dictates the material properties.
This gives engineers an advantage because the properties can be built into the laminate during fabrication.Isotropic Vs. Orthotropic
Iso – Properties are the same in all directions
Ortho – Properties are not the same in all directions.
- With Fiber Composites the fiber orientation dictates the material properties.
This gives engineers an advantage because the properties can be built into the laminate during fabrication.
5. Fabrication
6. Layers of a Composite Tube
7. Modeled Tube in ANSYS Model of Tube.Model of Tube.
8. Element Coordinate System Shell 91 From ANSYS Element Library
9. ANSYS Coordinate System for Shell Element
10. ANSYS Element Coordinate System
11. ANSYS Model SetupConstrained with Point Load
12. ANSYS Model SetupConstrained with Uniform Load
13. Real Test on Composite Tube
14. Filament Wound Tube
15. Deformed and Un-deformedPoint Load with 90o Fiber Orientation
16. Von Mises PlotPoint Load 0o Orientation
17. Von Mises PlotPoint Load/90o Orientation
18. Von Mises Graph of 90o/Hoop Orientation
19. Von Mises Graph of 0o/Longitudinal Orientation
20. Von Mises Plots of Uniform Loading with Different Orientations
21. Displacement of Point Loaded 90o/Hoop Orientation (Maximum Displacement 4.934mm)
22. Displacement Related to Orientation Uniformly loaded hoop has greatest displacement.
Combination of layers decreases displacement.
Displacement related to stiffness.
23. Results of Changing Orientation Hoop or 90o orientation is strong under transverse loading.
Longitudinal or 0o orientation is stiffer in bending.
Combination of orientations increases stiffness and strength.
24. Difficulties with ANSYS Creating model is not straight forward and simple.
Meshtool does not recognize that all element axis should coincide within each layer.
ANSYS is too powerful for simple problems.
25. Advantages of ANSYS Changing material properties or layer orientation is simple.
Many different orientations can be analyzed in a short amount of time.
ANSYS can predict results before fabricating composite sample.
Complex geometries can be modeled and evaluated easily.
26. New Ideas Analyze tube in torsion.
Apply moment instead of load.
Test as a pressure vessel.
Model unique geometries and compare results.
Model a beam or flat plate and compare with actual results.