Fusion 360: professional CAE software for 20€/month

Fusion 360: professional CAE software for 20€/month

As mentioned in this blog some weeks ago, CAD is moving on the cloud. A “new” player in this market is Autodesk’s Fusion 360. It would be difficult to describe all the features of this revolutionary tool here, so visit this link. If you are not convinced yet, see:

Not enough? They have a big active user community, a good technical support and you can write scripts with an API:


You may or may not like Autodesk’s decision to stop selling perpetual licenses, but you have to admit that 20 €/month for Fusion 360 is a good price. Yes, I said 20€.

A last important detail for FEA user: you can do “direct modeling” on imported parts. But I let this for another post…


For all those reasons, Idra Simulation decided to adopt it. This option is more flexible than the expensive licenses of SolidWorks, Creo and cie (their maintenance fees alone are more expensive than Fusion 360); and the few active open-source CAD projects are not yet ready for the industry.

Proof of Concept test for electric water heater

Proof of Concept test for electric water heater

This animation shows a proof of concept geometry for an electrical water heater:

Two graphite electrodes are immersed in a water tank. Three physics are involved. First, the static current conduction equation is resolved. Then, Joule heating energy is calculated in the entire geometry and used as a body force for the heat equation. Finally, temperature calculated is introduced in the Navier-Stokes equations.

For training or consulting using Elmer, contact us.

Numerical study of shrink ring and die interference

Numerical study of shrink ring and die interference

Prestressing technique is used to decrease the tensile stresses that develop in a metal forming die (powder compaction, extrusion, stamping, etc.). In order to increase die life and to protect the shrink ring, the interference value between the two parts must be optimized.


Die and shrink ring geometry

The iterative variation of the design parameters (interference, diameters, material properties) using numerical simulation leads to a reduction of time and resources invested. This process can be automated with Code_Aster in order to obtain an optimal design.

The tendency is usually the following: a higher interference leads to lower tensile stresses in the die during compaction, but to a higher stress in the shrink ring. Consequently, the optimized interference should be find to take advantage of the pre-stress tensional state of the die, without damaging the shrink ring. The failure of the shrink ring would reduce the fatigue resistance of the die.

The maximum principal stress for interference values of 0.05, 0.1 and 0.15 mm are shown on this image (section in the middle of the compacted part):


Download the “white poster”: Die_prestressed.pdf

For training or consulting using code_aster, contact us.

Code_aster adaptive meshing

Code_aster adaptive meshing

code_aster integrates an automatic adaptive mesh algorithm based on error estimation. The idea is simple: where the error is important, the mesh is refined; where the error is small, the mesh is coarsened. The mesh is adjusted until the convergence criteria is reached:



Adaptive meshing of a simple 3D geometry. Error estimation is based on the residual. Convergence criteria is the principal stress values.

Error estimator on the initial mesh

Error estimator on the initial mesh (the value of the error estimator has no direct physical interpretation)

For training or consulting using code_aster, contact us.

CAD on the Cloud

CAD on the Cloud

The trend is to develop Cloud Applications, and CAD programs are no exception to the rule.

Onshape is the first (to my knowledge) cloud-based CAD software. It makes data management very easy, and has an important data base of models shared by the users. It’s free to use if you accept to make your models public. This can be an issue for industries, so a paid version is also available.

They pretend to be “The future of CAD”, and I think they may be right!