Tips & Tricks

Model clipping feature in CFD-VisCART and CFD-GEOM

For better visualization of the geometry and mesh, a model clipping feature was introduced in CFD-VisCART and CFD-GEOM V2013.0. The following sections illustrate the usage and benefits of this feature.

Improve Productivity Using Scripts [Video Format]

As simulations become more integrated with the design process, engineers often spend time on repeated operations that do not contribute to their productivity. There is a need for tools that could capture, preserve and transfer the knowledge within the organization or to its customers.

How to report and talk about simulation time in an objective manner

Reporting or talking about simulation time is a difficult subject. In the article a way to manage this problem in an objective manner is given.

Materials in the database - Which material properties to use with respect to the three methods to simulate the heat effects of welding

A material is described with exactly one set of material properties. In simulation engineering - depending on the applied method and the moment in time when the simulation is carried out in the product development cycle - only subsets of a full material data set might be required. In this article is outlined which subset is used for which purpose, what is available in the database, and what can be simulated.

The transient method – the third out of three methods to simulate the heat effects of welding

In order to meet different requirements from first design to start of production, three different methods are available in the Virtual Welding & Assembly Suite from ESI. The third one – the transient method – is used when not only distortion but also residual stresses and microstructure need to be evaluated. The part size allows running a heat source gradually. Compare it with a formability evaluation in sheet metal forming. A motorcycle rim may serve as an example.

The instantaneous method – the second out of three methods to simulate the heat effects of welding

In order to meet different requirements from first design to start of production, three different methods are available in the Virtual Welding & Assembly Suite from ESI. The second one – the instantaneous method – is used when not only distortion but also residual stresses and micro-structure needs to be evaluated, but welded designs are so huge that it would make no more sense to use a classic transient method with a moving heat source – the simulation time would be too long. Compare it with a feasibility evaluation in sheet metal forming. A frame as produced in machine building, with more than 100 welds, may serve as an example.

The shrinkage method – the first out of three methods to simulate the heat effects of welding

In order to meet different requirements from first design to start of production, three different methods are available in the Virtual Welding & Assembly Suite from ESI. The first one – the shrinkage method – is used in the feasibility and planning phase. Goal is to get as fast as possible an estimation. Compare it with a one-step method in sheet metal forming.

Boundary layer meshing with CFD-ACE+ [video format]

The accuracy of a CFD solution is strongly dependent on how well the mesh resolves geometry and flow features. This is especially true for near wall regions (boundary layer) where viscous forces are not negligible compared to inertial forces.

How to check what software version you are running

There is a very fast and easy way to verify what software version you are running for your ESI CFD applications. You most likely know that this information is available for the GUI by clicking on 'Help → About ...', and for solvers by looking in the output file.

Always Make Sure You Have a Good Mesh Quality

The mesh has a great influence on the solver convergence and solution of every CFD Simulation. The user is strongly advised to check the quality of a numerical mesh.