Meshing Error—General Error/Mesh Failure on an Invalid Model

Issue

The process of interpolating Autodesk® Simulation CFD results to an FEA model either produces incorrect values or fails with errors.

Solution

Use the following diagnostic technique to identify the problem location:

From a command line, navigate to Autodesk® Simulation CFD installation folder, and type in the following. This produces a file that contains the locations of the nodes in your FEA mesh:

<FEAexecutable.exe> c:\directory_structure\file.ext -1

where:

<FEAexecutable.exe> is one of the following, based on your FEA tool:

iaba2cfd.exe : Abaqus
ians2cfd.exe : Ansys
icos2cfd.exe : Cosmos
ifem2cfd.exe : FEMAP
inas2cfd.exe : Nastran
iunv2cfd.exe : I-Deas

file.ext is name of the FEA file

directory_structure is where the FEA file (.inp for Abaqus, .cdb for Ansys, .gfm for Cosmos, .neu for Femap, .nas for Nastran, .unv for Ideas) is located.

For example: For Ideas, a "unv" file is called “valve.unv”. The command is:

iunv2cfd.exe c:\directory_structure\valve.unv -1

The result is an ".int" file that contains the x,y,z coordinates of the target interpolation.

A good technique for determining the problem is to enter some of the coordinates from the "int" file into the Monitor Point dialog in Autodesk® Simulation CFD.

If the points are very far away or always close to the origin, the unit system is probably incorrect.

If the points appear to be in the wrong location, the two models are probably not in the same location. The Autodesk® Simulation CFD and FEA Model origins are not aligned. If the CFD simulation is complete, it is probably easier at this point to correct the location and/or orientation of model in the FEA system.