Introduction

This document descibes the interface program between the FEMGEN grid generator and the PHOENICS CFD analysis code. This is a revised interface and users of versions of FEMGEN/FEMVIEW older than 2.3-09 should use the previous version of this document
(FGV2.3/PHOENICS/2.05).

The interface program has three methods for converting models from FEMGEN to PHOENICS. The technique used depends on the version of PHOENICS that is being interfaced to and the type of grid to be transferred. The conversion methods used are:-

1.

PHOENICS grids are translated by resolving the connectivity between FEMGEN bodies. This is the method used in versions of FEMGEN before 2.3-09. This method produces PHOENICS Q1 and XYZ files that are valid for PHOENICS version 1.5 and above. Only PHOENICS monoblock grids can be translated using this method. The use of FEMGEN and the interface program using this technique are detailed in the previous version of this manual (FGV2.3/PHOENICS/2.05).

2.

PHOENICS grids are translated using the CHAM GENIE library. This method looks at the connectivity between the elements and produces PHOENICS Q1 and XYZ files that are valid for PHOENICS version 2.1.

3.

PHOENICS grids are translated into the PHOENICS PEN format files. These files must be converted into Q1 and XYZ files using the PHOENICS GENIE system.

The program runs from within the FEMGEN executable and is invoked by the command UTILITY WRITE PHOENICS [filename], where `filename' is an optional parameter specifying the name to be used for the PHOENICS GRID file. The Q1 file name is generated automatically and is deduced from the grid file name.

The terminology used in this manual may be unfamiliar to PHOENICS users, as FEMGEN is primarily concerned with the generation of Finite Element Models and of Finite Element `Meshes', and the language of this manual reflects that fact.

Nevertheless FEMGEN can be used to advantage to generate PHOENICS models. PHOENICS `grids' are generated in terms of eight noded brick elements (cells) called HE8's and 4 noded quadrilateral elements called QU4. The corners of the elements are nodes defined by x, y and z coordinates. The command language and the program display are also expressed in terms of a mesh consisting of nodes and elements, but this command language may be customised by the user by defining `synonyms' whereby a command defined by the user may be mapped to one or more FEMGEN commands.

The results of a PHOENICS analysis may be transferred to the FEMVIEW data base, and viewed within FEMVIEW, and the reader is directed to the manual for the post-interface from PHOENICS to FEMVIEW ( Document : FGV2.3/PHOE2.1/Version 1.33 ). Thus a PHOENICS user can have integrated pre and post processing using the FEMGV software.