Contents of 'What's new in PHOENICS May 2009'

Changes Common to VR Editor and VR Viewer

Changes to VR Editor

Changes to the Earth Solver

Changes to VR Viewer

Changes Common to VR Editor and VR Viewer

Each Clipping_plane object consists of 3 OpenGL clipping planes. A maximum of two such objects are allowed, as there are only 6 clipping planes. The first Clipping plane object is created at the origin, and clips everything 'behind' it. This is the left-hand object above. The second Clipping plane object is of type 'High end clipping plane' (on the Options tab), and is originally located at the far end of the domain This is the right-hand object above. It clips everything 'after' it. They can be moved and rotated at will to provide a better view inside objects.

Clipping plane objects can also be created from 'Settings - New - Clipping plane' on the Environment Settings menu, or 'Object - New - Clipping plane' on the Object Management Dialog. When created in the Editor, they will be written to the Q1 like all other objects. When created in the Viewer, they will disappear when the Viewer is exited.

Clipping plane objects never affect the grid, and have no influence on the solution.

Changes to VR Editor

wind.gif (38447 bytes)

The wind object is very closely related to the wind_profile object described here. Only one Wind object is allowed, and it always fills the entire domain. Based on the wind direction it creates inflow boundaries at the domain edges using logarithmic or power law profiles on the upwind faces, and fixed pressure boundaries on the downwind faces. In addition, the upper, or sky boundary can also be made into a fixed pressure boundary.

The 'Ambient pressure' and 'Ambient temperature' entries set the pressure and temperature prevailing outside the domain. These values can be used, if desired, to set the external pressure and temperature at all INLET, WIND, WIND_PROFILE, OUTLET, FAN and PRESSURE_RELIEF objects.

When 'Initialise from ambient' is set ON (the default), the initial values of pressure (P1) and temperature (TEM1) are always made consistent with the ambient values set here.

When 'Set buoyancy from ambient' is ON (the default), the reference temperature for Boussinesq buoyancy is set to the ambient temperature, or for density_difference buoyancy, the reference density is calculated from the ambient pressure and temperature.

Object type:

> OBJ, PATCHES,  patch1, patch2, patch3, patch4, patch5
patch6, ... patchn

The PATCHES attribute contains a list of the patch names associated with this object. As many PATCHES lines as needed to hold all the patch names can be used.

All settings relating to the PATCH and COVAL statements linked to a user-defined object are printed in the relevant Group - these can be Groups 11, 12, 13, or 23. The name of the controlling object is written as a guiding comment.

The first location argument of PATCH (usually IXF) is set to -1, to indicate that the patch is to be linked to an object. The remaining five location arguments are zero. As many PATCH commands can be attached to one user-defined object as required.

In earlier (pre-2009) versions the IXF location argument was used to hold the object number. This method is still recognised on reading a Q1, but when the new Q1 is written the object number will be replaced by -1, and the patch name will be echoed in the PATCHES list.

The solver used for each variable can be switched between the default Stone-type solver, and an alternative conjugate-residuals-gradient solver.

The 'Terms in Equations' section has been moved to a separate panel.

Changes to the Earth Solver

The InForm INFOB command can be used to create a PLANE object, which can act as an angled plate.

    Graph options Dialog

Changes to VR Viewer