Learning Forum

[mateusz.urbaniak]

Hi,

 

im a formula student engineer and I've started working on composite simulations.

 

Im trying to simulate sandwich structures and I want to achieve best results by defining the materials we use, since in engineering data source there is a limited choice. I also want to validate the results with existing structures.

 

I've just learned about ansys granta edupack and I am on my way to getting a licence for that. Is it any good for my application?

 

We use Angeloni gg200t for example and some Toray based fabrics. We use resin infusion process using epoxy resin. I have datasheets for every material.

 

How and what information do I have to input to Ansys to achieve best results and acurately simulate our existing laminates?

[JP-Ansys]

Hi mateusz.urbaniak,

Thank you for reaching out to us regarding this question. 

If you are simulating the structural or thermal behaviour of composite structures you should use Ansys Composite PrepPost (ACP) which you can launch from Ansys Workbench --> Simulating Composite Structures with Ansys Composite PrepPost. With ACP you can - among other things - design and analyse such layered composites. It helps you capturing fiber orientation, inspect the models for specific failures and parameterize your model to find e.g. the best stacking sequence for you application. In fact we already have a free learning resource on modelling a CFRP monocoque using ACP that could be helpful to you --> FSAE Composite Monocoque Chassis | Ansys Courses.  

In order to run those simulations with ACP you need specific (additonal) material properties that need to be defined in the Engineering Data of your ACP(Pre) component system --> 4.1.1.4. Properties. It is of note that with the installation of ACP a new material catalog named Composite Materials is additonally available in the databank. The constituent material properties (fibres, fabric, resin, sandwich-core, etc.) are required to define the stackup or sublaminate properties using laminate theory --> 2.1.3. Material Data. Thus, you are advised to directly use the datasheets of your supplier to best inform the underlying material model of your FEA. Here is a great tutorial of a basic/advanced sandwich panel simulation in ACP considering carbon fiber reinforced plastic (T700) and a foam core --> Chapter 1: Basic Sandwich Panel Tutorial/Chapter 4: Advanced Sandwich Panel Tutorial.

Regading your question on using the materials data provided in Ansys Granta EduPack or Ansys Granta Selector (provided as part of the Ansys Student Team sponsorship: Free Software for Student Design Teams | Ansys Partnership): Of the 4000+ material entries in the MaterialsUniverse data, there are approximately 70 entries pertaining polymer matrix composites like the ones you are working with. The properties associated with these represent in-plane characteristics of the dominant/primary fibre orientation rather than the true anisotropic properties that would be required for Ansys ACP. It must be noted that these reflect the material's maximum performance and are thus not conservative. However, if you are in the early stage of your design development you may save a lot of time during this exploration phase by assuming (quasi-) isotropic behaviour and using Ansys Mechanical instead of Ansys ACP. Likewise, both Ansys Granta products have a synthesizer tool which allows you to predict e.g. the performance of balanced sandwich structures for different face-sheet and core combinations (assuming perfect bonding) and different load cases. This way you can also infer a good estimate in the early design stage. Nevertheless, I'd always recommend using Ansys ACP to verify your design exactly (anisotropic material properties, stacking sequence, etc.), i.e. achive best results and build confidence in your simulation before going into production. On that note, Ansys Granta Selector does also have advanced (industry-standard) databases such as the Firehole Composite Database with over 400 grades of continuous fibre reinforced polymers which have - among other things - direction-dependent properties which are required for anylses with Ansys ACP. Lastly, you may find this free student team resource on Ansys Granta Selector useful: Material Selection and Eco-Analysis for Chassis Using Ansys Granta Selector | Ansys Courses

I'd recommend checking out the free Ansys Innovation Courses for further knowledge material: Ansys Innovation Courses | ANSYS Innovation Space. 

I hope this helps you succeed!

[mateusz.urbaniak]

Thank you for the reply because it definitely helped. I will try to get Granta from my licence provider. Getting to know laminate theory is also a good starting point, I just need to get my customer ID somehow to access the link. I'll just ask my provider as well.