Tips & Tricks

3D/Multiconductor Transmission Lines (MTL) Coupling VS. Stand-Alone FDTD (Accuracy)

This article is aimed at comparing the 3D/Multiconductor Transmission Lines (MTL) coupling accuracy with the PAM-CEM/FD stand-alone use, when applied to simplified wired models. Recommendations for good agreement are also proposed.

Weld Fatigue analysis based on the Dang Van Criteria

Numerical modeling of fatigue behavior has become critical for welding applications. For this purpose the ‘Dang Van criterion’ has been integrated in SYSWELD for fatigue evaluation of welded structure under multi-axial loadings. The Dang Van fatigue damage criterion is used to predict crack initiation and life duration of components subjected to damaging load. This criterion is based on multi-scale approach which assumes that shakedown occurs before crack initiation.

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 challenge of simulating casting and heat treatment

Foundries that have implemented casting simulation to shorten development time, further wish to use simulation in order to reduce the cost of subsequent processing steps. This often requires the simulation of heat treatment.

CFD-FASTRAN/CFD-ACE+ coupling for thermal environment simulations

In certain applications, different regions of the computational domain experiences flow conditions that are so different that it is very difficult for a single solver to produce accurate results at the extremes. In many situations, such problems can be separated and solved using loosely coupled solvers. Each solver is chosen to provide highly accurate solutions for the prevailing flow conditions.

Avoiding Chimera Errors in CFD-FASTRAN

This note discusses a common error encountered by users when trying chimera meshes in CFD-FASTRAN. Such errors are easy to avoid and hopefully this note will assist you.

Motion Model Dependencies in CFD-FASTRAN

Moving-body models available in CFD-FASTRAN are highly suited to simulate complex prescribed and six-degree-of-freedom (6DOF) motions of rigid bodies. In many engineering problems, this translates to multiple bodies moving relative to one another.

Low Mach Preconditioning and Dual Time Stepping in CFD-FASTRAN

Density-based schemes employing time-marching procedures available in CFD-FASTRAN provide excellent stability and convergence characteristics for high-speed compressible flows (typically M >0.5).

Axisymmetric 2D Convergent-Divergent Boattail Nozzle Simulation Using CFD-FASTRAN

The NASA D-1.22-L boattail nozzle configuration was obtained from the MADIC (Multidisciplinary and Design Industrial Consortium) program. The geometry definition and the flow conditions are documented in NASA TP 1766 [1]. This user tip presents a validation of numerical methods against experimental data.

Chemical-kinetic Model for Mars Atmosphere Re-entry Applications

The shock layer flow over a blunt body entering a planetary atmosphere at a hypersonic speed will dissociate and partially ionize. A reliable prediction of the flow-field for such application requires a chemical-kinetic model. For Mars atmosphere, the five species Park'94 is considered [1]. The dissociation of CO2 is producing C, CO, CO2, O and O2.