How to specify carbon fibre material properties in ANSYS ACP

[Jason Clark]

Hey there, my honours year thesis is on the design and analysis of a carbon fibre wheel for a Formula Student racecar. However, I am unable to obtain carbon fibre material properties to input into the Engineering Data section. I am required to specify the Youngs Modulus in the x, y and z directions and the Poisson's Ratio and Shear Modulus in the XY, YZ and XZ directions. However, I cannot find any data for carbon fibre that specifies these properties in each direction - all I can find is a single tensile modulus value for the fibre. Does anyone know how to find these properties in each direction for carbon fibre?

Many thanks
Jason

 

[dreens]

Hi Jason,

Like any "fiber", carbon fiber material is going to be highly directional in its material properties. In fact, a quick glance online shows that you can buy carbon fiber with different fiber arrangements: http://oribimanufacturing.com/uni-directional-vs-woven/. I'm guessing you'll want to orient your fibers along the radius of the wheel, and have it configured in a primarily tensile stress configuration? If you're doing this, maybe you can still get meaningful information out of your simulations by putting the fiber tensile strength in for one of the young's modulus dimensions, and just putting something much lower than real life (factor 100) in the other directions. If it ends up yielding in those weak directions, you'll have to figure things out more precisely, but if not then you know you're in the clear.

If you know how you want your fibers oriented, I would find a supplier and bug them for the engineering data.

 

[Mech_Engineer]

Composite materials are modeled in ANSYS using layered composite elements, which take as inputs the orthotropic material properties of the layers, as well as the number of layers and the orientation of each layer. This is a fairly well-developed type of analysis and most FEA packages will support some form of orthotropic material and/or composite material analysis.

There is some more reading here on the subject of composites in ANSYS: https://support.ansys.com/staticass...s/Composites and ANSYS Composite PrepPost.pdf