Today the use of CAD is commonplace in Engineering.Furthermore, companies that do use CAD tend to either use 2D CAD (AutoCad etc) or 3D Solid Modelling (SolidWorks, Inventor etc)The ‘2D Users’ are using CAD as, essentially, an electronic drawing board and this is quite often still the best way to transfer information for manufacturing. 2D is widely used in Shipbuilding, Offshore, and Civil Engineering.The ‘3D Users’ are using CAD, generally, to create Solid Models and may produce 2D drawings from the 3D part or manufacture directly from the CAD model (NC, STL etc). This is commonplace in the Automotive sector for example. Unfortunately, neither of the above approaches are optimum if you wish to perform FEA of a Composite structure!What is required is a hybrid approach to CAD modelling. A ‘2.5D’ CAD modelling method. Surface Modelling!Why?Most Composite FEA is conducted using Elements that have their thickness defined in a table and not explicitly modelled (as per a 3D CAD model). Therefore a Surface CAD model is generally created to aid FE Mesh creation.Creating a Surface Model for FEA is actually more complex than creating a Solid Model. Decisions have to be made regarding the way surfaces meet, for example, that are just not considerations in Solid Modelling. Add to this the fact that most Designers either have never created Surface Models or don’t have the tools to create them and you have a potential problem. (Lots of the popular Solid Modellers have poor, or non-existent, Surface Modelling tools)For further information read on.
Today the use of CAD is commonplace in Engineering.
Furthermore, companies that do use CAD tend to either use 2D CAD (AutoCad etc) or 3D Solid Modelling (SolidWorks, Inventor etc)
The ‘2D Users’ are using CAD as, essentially, an electronic drawing board and this is quite often still the best way to transfer information
for manufacturing. 2D is widely used in Shipbuilding, Offshore, and Civil Engineering.
The ‘3D Users’ are using CAD, generally, to create Solid Models and may produce 2D drawings from the 3D part or manufacture directly
from the CAD model (NC, STL etc). This is commonplace in the Automotive sector for example.
Unfortunately, neither of the above approaches are optimum if you wish to perform FEA of a Composite structure!
What is required is a hybrid approach to CAD modelling. A ‘2.5D’ CAD modelling method. Surface Modelling!
Why?
Most Composite FEA is conducted using Elements that have their thickness defined in a table and not explicitly
modelled (as per a 3D CAD model). Therefore a Surface CAD model is generally created to aid FE Mesh creation.
Creating a Surface Model for FEA is actually more complex than creating a Solid Model. Decisions have to be made
regarding the way surfaces meet, for example, that are just not considerations in Solid Modelling. Add to this the fact
that most Designers either have never created Surface Models or don’t have the tools to create them and you have a
potential problem. (Lots of the popular Solid Modellers have poor, or non-existent, Surface Modelling tools)
For further information read on.
