STEP 2
Results are stored in the DTF file. When you start CFD-VIEW go to the open
file menu, click DTF and use filter to locate
tutorials or demos subdirectories and files with .DTF extensions. Click the
right file and open it. Notice that demo problems are only
represented by DTF files and tutorial problems contain a variety of other
files. Make sure that you are in tutorial /results subdirectoory.
DTF file is also used to keep the geometry and model setup parameters. Data
(in the form of scalars and vector variables) is only
added there during and after the simulation.
So you have a geometry outline on your screen. It does not look very informative
and it is not very clear how to manipulate the image.
Make sure that you have 3 button mouse! If you do not - STOP HERE and go
and buy one. Cheapest 3 button mouse costs $5-10.
Middle button allows you to zoom in and out. Press middle button and move
mouse forward and backward. You will see what I mean.
Then press the left button and move mouse left and right, up and down. That
will teach you how to navigate your gemetry object using
so-called "virtual trackball" concept. You may find it difficult to rotate
and precisely position images. Yes, this is how it is. I promise that more
you
do it - easier it gets.
You may have noticed that you have an attribute bar (on the bottom of CFD-VIEW
screen) with Surface and Primary menu buttons.
If you click Primary button you will see the list ov variables that were
included in this SPECIFIC DTF file. Note that user has options to specify
variables he wants in the output. CFD-PLASMA list of outputs can sufficiently
exceed the vertical length of the screen. So be advised that
these are only some of the possible outputs and some variables that you care
about may not be in the list. Later on we will tell you how to add them
there.
Just be patient for now. Click with the mouse (left button) on the variabe
you are interested in. Go to Surface button and click on the
FLOODED button. Make sure that GEOM-object (lower right hand side of the
screen-Object box) is also picked. [CFD-VIEW automatically creates a Geometry
object when you first load a data set. Initially, only the Geometry object
outline is drawn.]. By now you can see a nice color plot of ....say plasma
density Ne (assuming that you have picked Ne in Primary menu). If you have
not, please go back to Primary and pick Ne. Everything looks good, but you
are missing color legend. So, click "Annotation Object"
[red A button in upper right corner]
and legend button. Now you have image, legend and
need to learn how to
a) save the image
b) use different units (if you want to)
c) change range of the colormap (to nail ranges you your interest)
b) move legend bar closer to the image
To save the image go to "Save IMAGE AS" button (left upper corner) and specify
8bit BMP (this is common format
for Windows, allows easy import in Powerpoint, Painbrush and any other software.
If you read bmp into
Painbrush you can resave it as GIF or JPEG (if you want to. GIFs are usually
smaller than bitmaps-BMPs).
Go to GIZMOZ menu, click on Calculator button. Type in the calculator
Ne1=Ne/1E6 and press enter button. You had just created a new vatiable Ne1
which represents Ne in 1/cm3 units
instead of 1/m3 units. Now you are no longer surprised that electron density
is so HIGH ! Go to PRIMARY
menu and click Ne1 instead of Ne. You will see that legend and image on you
screen were just adjusted correspondingly.
And you just learned how to create new variables with the calculator. In
plasma simulations a lots of auxillary variables
can be derived by simple algebraic post-processing of existing fields. For
example total pressure in the chamber is
equal to the sum of pressure and electron pressure. Go to calculator and
type Pe=Ne*xxx, hit enter and visualize
electron pressure field. Go back to calculator and type PChamber=Pe+P, hit
enter and visualize PChamber.
Cool stuff?!
Click on the Legend-object (low right corner, Objects Menu). You now see
4 green squares around the legend bar.
Position mouse in the middle of one of these green squares and double-click
left mouse button and hold it. You
will see a little cross on top of the green square. Drag mouse and you will
see that legend-object is stretched and
moved. Go to another corner and repeat the operation. Position legend menu
closer to the image and stretch it
to your liking.
Now you can save the image. After you press save as button a little corner
will appear pointing the upper
left corner of the image. Move mouse to point lower right corner of the image.
CFD-VIEW will save the image.
Check that file was indeed saved and is in the subdirectory. If the upper
corner was not in the right place
then move mouse to the "right place" and repeat the "Save As" operation.
So now you are ready to postprocess your CFD-PLASMA scalar fields and document
the results of your work.
It is time to learn how to process VECTOR Variables.