Tips & Tricks

Hints on the usage of linear Tetrahedron (TETR4 / ) elements

This tip provides some background information on the question, when, or when not, to use the linear tetrahedron (TETR4 / ) element in Virtual Performance Solution (VPS)

Why do total mass, sum of part masses and sum of nodal masses not match ?

This tip discusses the possible discrepancies in informations concerning total mass, part masses, nodal and element masses, given in the Virtual Performance Solution (VPS) output listing.

Which moments of inertia to use in added mass (MASS / ) cards ?

This tip discusses the choice of physically meaningful numbers to be used, when moments of inertia need to be specified in an added mass definition.

Some possible problems with CNTAC or TIED definitions

This tip discusses some of the reasons that might be responsible for problems with contact or tied definitions in a VPS simulation

Relation between Bulk Modulus K, Shear Modulus G, Young's Modulus E and Poisson's ratio ν

This tip explains the relations between the parameters that describe the linear elastic behavior of materials

How to convert force-deflection into true stress-strain curves?

This tip helps to convert typical tensile test data into stress-strain curves to be used in many material models of Virtual Performance Solution (VPS)

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).