There are two possible interfaces for the Viewfactor results in the form of the radiative resistors in the VFRESDAT file and the radiosity nodes in the VFNODEDAT file to the Patran Thermal analysis module. The first of these is the use of the data as input to the thermal network analysis code QTRAN and the second is through a translator in PATQ to change the binary form of the radiative resistor file to text form readable by the user. Refer to the MSC.Patran Thermal User’s Guide, Volume 1: Thermal/Hydraulic Analysis for more information on PATQ and QTRAN.

To include the thermal radiation network data from Viewfactor in the Patran Thermal analysis by QTRAN, the user must include the two files from Viewfactor (VFRESDAT and VFNODEDAT) in the QINDAT file for QTRAN. This is typically done by using QTRAN’s $INSERT command in the QINDAT file.

If you are not using the standard filenames, then you need to substitute the filenames in use at the time.

The VFNODEDAT file should be included in the QTRAN QINDAT. See VFNODEDAT, 102. This is done with the line

This line must be in the QINDAT DEFNOD section, that is before the $ sign terminating the section and typically after the $INSERT NODEDAT line.

The VFRESDAT radiation resistor data file should be included in the QTRAN QINDAT, VFMSG, the Viewfactor Message File, 103: RESISTOR DATA SETS of the QINDAT file. This is done with the line

A sample QINDAT file is shown with the parts relevant to the Viewfactor files VFRESDAT and VFNODEDAT shown in bold. This example was created on a VAX VMS computer platform. If you have a different platform, see your MSC.Patran Thermal User’s Guide, Volume 1: Thermal/Hydraulic Analysis for the system dependent file names.

This capability is provided so that you may examine the contents of the radiation resistor file in text form. In general, this is not very practical due to the very large number of resistors created for the typical thermal analysis model.

The MSC.Patran Thermal User’s Guide, Volume 1: Thermal/Hydraulic Analysis provides more complete information on the Patran Thermal program PATQ. Here you need only be concerned with the aspects of PATQ which relate to translating a VFRESDAT file in binary form to a VFRESTXT file in text form.

The translation process is fairly simple. PATQ is an interactive menu-driven program with prompts for user input when required. Many of the prompts have default values that will be used if just a carriage return is entered. PATQ also generates diagnostic error messages if it detects any problems during the interactive session.

You are cautioned that the resulting text file, VFRESTXT, will be much larger than the binary version of the data. You may wish to ascertain if this much disk space is available. If the files are of significant size, the translation may take a significant amount of time and this process is interactive.

The procedure of translating a binary VFRESDAT file to a text file VFRESTXT using PATQ is fairly simple and is reproduced here as a sample.

There are of course many different options in the translation process and they cannot all be presented here. The following dialogue is typical of a PATQ translation. If errors are detected by PATQ, error messages will be written to the terminal screen.

Refer to the MSC.Patran Thermal User’s Guide, Volume 1: Thermal/Hydraulic Analysis for help in interpreting the data in the VFRESTXT file.