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.

Process optimization: the future of numerical simulation software

Optimization is becoming a very popular word. However, what does it mean and what does it involve? The goal of this e-tip is to give some keys about optimization concepts and its use in process optimization. In a first stage, we will describe the type of optimization problems that could be solved and in a second stage, the principles and algorithms will be presented. Finally, advantages and drawbacks of the different methods and algorithms will be addressed, with respect to the different types of optimization problems which can be solved.

Casting simulation: from prototype to performance

Passenger safety in cars, planes and other transportation vehicles is an ethical obligation, a legal issue and a technological challenge. Simulation is a well implemented tool in order to test the behaviour of a car body during crash. The models, including rapid deformation and rupture, are sophisticated and reliable. Currently, most properties used in such simulations correspond to homogenous and defect free materials. However, cars are manufactured before being crashed. And manufacturing routes such as casting, but also stamping, forging or welding, do not provide defect free and homogeneous materials.

Parallel processing

“To pull a bigger wagon, it is easier to add more horses than to grow a gigantic horse.” This paraphrased quotation nicely expresses the basic concept of parallel processing. The speed of sequential computers has been doubling every eighteen months, according to Moore’s law. However, at any given time, that speed is limited by the state of the art in integrated circuit design and manufacturing. To circumvent that limitation, it is possible to split a given computationally intensive task among multiple processors working simultaneously.