QUAD 4 Shells: Obtaining Accurate Stress Results

In the Property form, you must enter values for shell top surface (Z1) [termed “Fiber Dist.1” in Patran]and shell bottom surface (Z2) [termed “Fiber Dist.2” in Patran] to obtain accurate stress results on those layers. If the shell midplane is not offset from the plane of the mesh (default condition) then:

  • Z1= +thickness/2
  • Z2= – thickness/2 (NOTE the negative sign!)

The positive Z-axis is in the same direction of the element normal.

If you do not input Z1 and Z2, you can Post out the Von Mises stress, but the stress components and principal stresses will be incorrect.

Temperature Interpolation:

Solution 1-4554102
The Patq Temperature Map utility is a very useful tool enabling the user to map temperatures from a thermal analysis to a structural or other model. The destination model must have the same or similar (within the tolerance distance) geometry. The meshes can be dissimilar and in separate databases. The transfer of data is accomplished using the neutral file system.

Usage Notes.
From your thermal model you will obtain a neutral file and nodal results file (e.g. therm_model.ntl and nr0.nrf.01)

From your structural model you will need to export a neutral file (e.g. struc_model.out)

Invoke patq and select menu pick 6 for utilities followed by menu pick 7 for Temperature mapping.

The utility will prompt you for your “FROM” neutral file (therm_model.ntl) and
your “TO” neutral file (struc_model.out)

Then you can input any name for the “MAPPED” neutral file name since this is an output from the utility. (patran.map)

The remaining required inputs are fairly self-explanatory and the defaults will work for most cases.

The utility then searches for “TO” nodes that are within the tolerance distance of the “FROM” nodes and requests the name of your nodal temperature results file (e.g. nr0.nrf.01).

The “MAPPED” file is then created (default name: patran.map) This is a neutral file that can be imported into your structural model. It will produce a spatial field and a spatial temperature LBC which will be in a new load case named based on your input for the SID number.

This sequence of operations can be performed more conveniently using a Patran shareware utility: Utilities, Loads/BCs, Temperature Interpolation
See also: Solution # 1-4554104

Solution # 1-4554104
The Patran Temperature Interpolation shareware utility is a convenient way to map temperature results from a thermal model to a structural model. It is found in:

Utilities, Loads/BCs, Temperature Interpolation

This utility runs the patq Temperature Map utility in background. And should be executed in the structural database after the separate thermal analysis has been performed and has produced the thermal neutral file (e.g. therm_model.ntl) and nodal temperature results file (e.g. nr0.nrf.01).

These two files are input in the Temperature Interpolation form along with the tolerance setting and the SID number for the new load case.

A neutral file need not be exported from the structural model when this utility is used. See also, Solution # 1-4554102 regarding using the patq temperature mapping utility.

Reading in results

Read Archive File

Read Archive File