Encyclopaedia Index

CAD Interface

In setting up a Computational Fluid Dynamics simulation, much of the task of data-input is simply defining the geometry of the mechanical structures within (or around) which the fluid flows. Yet these structures are often already well described by engineers within their chosen CAD systems.

With the PHOENICS Universal CAD Interface, the opportunity now exists for engineers to transfer geometrical data automatically into the PHOENICS Family of CFD packages as the starting point for the simulation.

CHAM has achieved this through the development of an interface which simply transfers wire-frame models in the universal IGES format supported by all leading CAD and FE packages, directly into the code

The interface is a translator which will read an ASCII format IGES wire-frame model and write the geometry into a PHOENICS Q1 file. This will provide the user with the initial data for the development of a grid using the interactive grid generation facilities within the PHOENICS menu system.

IGES ENTITIES TRANSFERRED:

IGES Entity No: IGES Entity Name: PHOENICS Entity:
100 Circular Arc ARC Line
102 Composite curve SPLINE Curve and Line
104 Conic Arc ARC Line
106 Copious Data SPLINE Curve and Line
110 Line Line
112 Parametric Spline SPLINE Curve and Line
  Curve  
116 Point Point
124 Transformation Matrix Applied to other entities
    before output  
126 Rational B-Spline SPLINE Curve
  Curve and Line

Any points and line that lie with the model tolerance will be merged into single entities.

Since CAD (and FE) packages almost all produce IGES files, the list of mechanical and structural design codes now interfaced to the PHOE Family of CFD codes is very large and includes:
AutoCAD ProEngineer Catia
Ansys Duct 5 CADDS
Matra Intergraph PATRAN*
I-DEAS*

(*specialised interfaces also available)

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