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How to obtain orthotropic properties for the 2x2 twill carbon fiber fabric

http://www.talkcomposites.com/Topic34915.aspx

By Abdel-Rahman Baraka - 2/25/2020 1:52:47 PM

Good evening, guys.
I'm currently working on modeling Carbon Fiber-Reinforced Polymer (CFRP) composite aerodynamic parts such as wings, endplates and nose, or any aerodynamic composite part that could be subjected to aerodynamic or mechanical loads using the Ansys ACP tool coupled with static structural. This is a part of work needed for the Formula Student UK 2020 competition which takes place annually in the Silverstone F1 Grand Prix Circuit in Northampton.
Long story short, I was wondering if someone could tell me how exactly to obtain all of these orthotropic material properties that Ansys needs to fully define a new material in its engineering materials database (Note: all of the yellow boxes mean that Ansys will not accept the material unless all of these boxes are filled: and to find all of these properties in x,y and z directions is a really strenuous endevour and time-consuming; it's not practical at all). As you can see in the attached picture, I was trying to add a new material (I named it: 2x2 Twill Carbon Fiber which we bought from Easy Composites), and in order to model its performance, I had to add orthotropic elasticity, orthotropic stress limits and orthotropic strain limits as well as density and ply type. Ansys already has woven carbon fiber in its database but I can't be sure that it's the twill weave type or that its properties match that of the 2x2 twill fabric that's sold here on Easy Composites and that we bought and are going to use. The only useful thing the datasheet provides is the density; other strength values are for the fiber itself not the fabric as per the testing standard mentioned in the datasheet itself. 
If anyone of you bright gentlemen/ladies could help me find these properties, we would very much appreciate it 
By Buchado - 2/25/2020 11:38:00 PM

Abdel-Rahman Baraka - 2/25/2020 1:52:47 PM
Good evening, guys.
I'm currently working on modeling Carbon Fiber-Reinforced Polymer (CFRP) composite aerodynamic parts such as wings, endplates and nose, or any aerodynamic composite part that could be subjected to aerodynamic or mechanical loads using the Ansys ACP tool coupled with static structural. This is a part of work needed for the Formula Student UK 2020 competition which takes place annually in the Silverstone F1 Grand Prix Circuit in Northampton.
Long story short, I was wondering if someone could tell me how exactly to obtain all of these orthotropic material properties that Ansys needs to fully define a new material in its engineering materials database (Note: all of the yellow boxes mean that Ansys will not accept the material unless all of these boxes are filled: and to find all of these properties in x,y and z directions is a really strenuous endevour and time-consuming; it's not practical at all). As you can see in the attached picture, I was trying to add a new material (I named it: 2x2 Twill Carbon Fiber which we bought from Easy Composites), and in order to model its performance, I had to add orthotropic elasticity, orthotropic stress limits and orthotropic strain limits as well as density and ply type. Ansys already has woven carbon fiber in its database but I can't be sure that it's the twill weave type or that its properties match that of the 2x2 twill fabric that's sold here on Easy Composites and that we bought and are going to use. The only useful thing the datasheet provides is the density; other strength values are for the fiber itself not the fabric as per the testing standard mentioned in the datasheet itself. 
If anyone of you bright gentlemen/ladies could help me find these properties, we would very much appreciate it 

Hi Abdel,
you can't run a simulation of a composite part with only the fiber/reinforcement properties.
The properties of a composite part depends on the fiber properties, the resin properties and on the fiber/resin ratio, even if you make a part from a 250GPa modulus carbon fiber fabric, it would have a lower modulus due the presence of resin.
Do some research on Rule of Mixtures, it's a good start point for composites parts properties.
If you want to look further into it, I would recommend ''An Introduction to Composite Materials", by Clyne and Hull, it's a nice book.

Give us some more details about it, will you build the part yourself? Or is it just the simulation?