Encyclopaedia Index

What's new in PHOENICS 3.3 Virtual Reality

An overview of improvements to VR-Editor and VR-Viewer is given below.

Developments and improvements related to other aspects of PHOENICS can be seen by clicking here.

  1. Body-Fitted-Co-ordinates in PHOENICS-VR
  2. Examples of BFC in VR-Editor and VR-Viewer
  3. The Virtual-Reality Editor
  4. The Data-Input Menu
  5. The Virtual-Reality Viewer

Body-Fitted-Co-ordinates in PHOENICS-VR

In PHOENICS 3.3, Body-Fitted-Co-ordinates (BFCs) are available within the VR environment. The VR-Editor can make the necessary boundary-condition settings, and the VR-Viewer can display the solutions. Further examples are shown here.

Mesh Generation

The BFC mesh must be generated outside PHOENICS-VR, and then imported.

The possible methods of mesh generation are:

All BFC library cases, and all user-generated BFC cases can also be loaded into PHOENICS-VR.

Further details are given in Chapter 12 of TR/326 PHOENICS-VR Reference Guide.

Object Creation

Apart from the differences noted below, objects are created and manipulated, and have the same attributes as in Cartesian and Polar co-ordinates.

Object Position and Size

The object position is given in terms of the I,J,K cell corner used as the origin of the object.

The object size is given in terms of the number of cells occupied in each (grid) co-ordinate direction.

Object Duplication

When an object is duplicated, a new object occupying the same number of cells as the original is created at the origin of the block containing the original.

Object Arraying

When an object or group is arrayed, the Pitch specifies the number of cells between origins.

Default Cliparts

In BFC, it is not possible to attach cliparts to objects. Objects take on the shape of the cells they occupy.

Colours are attributed to objects on the basis of their type.  It is not possible to change the allocated colours.

Results Viewing

Apart from the differences noted below, the VR-Viewer operates as it does for Cartesian and Polar grids.

Vector and Contour Slices

The Slice Direction X/Y/Z buttons now refer to the I, J and K grid co-ordinate directions, and not to the Cartesian space directions.

In a multi-block case, the contours and vectors are drawn for the block which contains the probe. If plots are required from more than one block at a time, the Create Slice button can be used to store the current slice.

The probe can be moved to the next block, another slice created, and so on until the entire picture has been built up. The contour and vector display in the saved slices always follows that of the current slice.

Streamlines

Streamlines can only be started at cell centres, because the probe only moves from cell-centre to cell-centre.

Examples of BFC in VR-Editor and VR-Viewer

Example 1: Flow in a Curved Air Conditioning Duct

Mesh generation in GeoGrid:
Geometry display, Boundary condition designation

Set-up in VR-Editor:
Geometry, Inlet, Outlet

Results viewed in VR-Viewer:
Vectors on centre-line, Cross-stream vectors, Temperature contour on centre-line, Temperature iso-surface, Streamlines

Results viewed in TECPLOT:
Vectors on centre-line, Temperature contour on centre-line, Temperature iso-surface, Streamlines

Example 2: Flow in a Stylised Intake Duct

Mesh generation by ICEM-CFD: Geometry shown in PHOTON

Set-up in VR-Editor: Geometry shown in VR-Editor

Results viewed in VR-Viewer:
Velocity vectors, Velocity contours, Streamlines

Example 3: Flow in a T-junction using an O-Grid Multi-Block Mesh

Mesh generation by ICEM-CFD:

Set-up in VR-Editor: Geometry shown in VR-Editor

Results viewed in VR-Viewer: Velocity Vectors, Pressure contours, Streamlines

Example 4: Pipe Flow with Unstructured Multi-Block (B582)

Mesh generation: PIL GSET commands in Q1

Set-up in VR-Editor: Geometry shown in VR-Editor

Results viewed in VR-Viewer: Velocity Vectors, Velocity contours, Streamlines, Pressure iso-surface


The Virtual-Reality Editor

General

The Reset Default Data button on the File menu has been replaced with Start New Case, which leads to a list of available Special Purpose Products.

The Edit button on the top menu bar now contains the items Domain attributes, Object attributes, Find object, and Editor parameters.

Autoplot has been added to the Run menu.

GeoGrid has been added to the Run menu.

Plant Menu has been added to the Run menu.

The top menu bar now has a Help button, which leads directly to the PHOENICS on-line  documentation.

The object-visibility attribute is now saved to Q1. Once an object is hidden, it remains hidden until the user displays it again.

The Hide and show toggle now has a right-mouse-button function, in which allows all objects of a given type to be displayed or hidden.

The Help entries accessed by clicking on the ? in the top-right of the window title bar, then clicking on the desired button or data entry field have been extended to the lower-level dialog boxes. In PHOENICS 3.2 only the top-level dialog boxes had help entries.

Object Creation Dialog Box

Image: Object Dialog Box

There are now strict checks on duplicate object names. All object names are upper-cased before use. If a duplicate object name is entered, the user can choose to modify the existing object of that name, or enter another name.

The 'Cancel' button now fully undoes all actions taken in all dialog boxes below the main object dialog box.

The 'Object affects grid' button determines whether an object creates region boundaries to coincide with its bounding box, or not.

Image: Object with matched Grid
Image: Object with Unmatched Grid

The default objects for Inlet, Outlet and Fan have been changed to be transparent.

The default objects used in cylindrical-polar co-ordinates have been modified to use the same colours as Cartesian and Body-Fitted co-ordinates.

Rotation Dialog Box

The three rotation angles, alpha, beta and theta are now real numbers with values in the range -360 -> +360. Previously they were integers in the range 0 - > 359.

Importing CAD Data

The CAD import button has been removed from the File menu of the Top menu bar, and placed on the Object dialog box.

Once a CAD geometry has been imported, it is possible to either resize the geometry to fit the VR object, or resize and reposition the VR object to fit the CAD geometry. This allows a CAD geometry consisting of several objects to be reassembled in the correct relative positions without user intervention. 

PCB dialog Box

The default material is Epoxy, but all other materials are now allowed. The non-isotropic conductivity feature can now be used to make a domain material 'thermal bridge' between two solid objects.

Pressure-Relief Object Dialog Box

The pressure-relief object is forced to occupy a single cell, closest to the origin, and the pressure coefficient is defaulted to 1000. In Version 3.2, the user had to take great care that the object used was neither so small that it would be ignored, nor much bigger than the nearest cell. Also, the default coefficient was only set when the Attributes dialog box was visited.

Fan Object Dialog Box

The Fan object can be switched between the default rectangular fan and a circular fan with swirl. The circular fan allows for a non-zero inner diameter.

Translation of Non-VR Cases

The translation of standard PIL Q1 files into VR-Objects has been further improved.


The Data-Input Menu

More detailed changes have been made 'below the surface' of the Main Menu. Many of these are the result of error-correction, or additional protection against conflicting settings or repeated changes of options. In particular:


The Virtual-Reality Viewer

The view and object-visibility settings are now taken more accurately from the VR-Editor. Objects hidden in the VR-Editor remain hidden.

The stream-line algorithm has been improved, so that streamlines do not end unexpectedly, or in some cases never appear.

The Delete streamlines and Delete slices buttons now allow a choice of Delete last or Delete all. A streamline or slice created inadvertently can thus be removed without losing the previous elements.

The iso-surface is no longer drawn inside blockages for variables which have no meaningful value there (e.g. pressure inside a solid).

The iso-surface value can be toggled between the probe value, and a user-specified value.

In a two-phase case, vector and streamline plotting can be switched between the phases. If temperature is stored, then Select Temperature will get the temperature of the current phase.

In multi-block BFC case, VR-Viewer displays results for the block containing the probe. As the probe is moved from block to block, so the display slice follows it. To build up a composite picture from several blocks, the slices in each block can be saved.

The error which caused contour plots to fill with red when the view was changed has been traced and repaired.