Boundary conditions

Symmetry Planes

We now have our main cavity discretised. In principle, we could now compute the resonant fields in it. But we better use the symmetries of the cavity. We have three symmetry planes: The cavity is symmetric with respect to the plane z=0, and to the plane x=0 and to the plane y=0.

We specify that we only want to compute in the volume $x \le 0, y \le 0, z \le 0$ by specifying the borders of the computational volume accordingly. We change the specifications in the inputfile to

 ###
 ### We define the borders of the computational volume,
 ### and we define the default mesh-spacing.
 ###
 -mesh
     spacing= eval(InnerRadius/15)
     pxlow= eval(-1.1*OuterRadius)
     pylow= eval(-1.1*OuterRadius)
     pzlow = eval(-(GapLength/2+TaperLength+9e-2))
     pxhigh= 0
     pyhigh= 0
     pzhigh= 0

When we feed gd1 with this inputfile (gd1 $<$ doris02.gdf) we get a screen similiar to the one shown in figure 1.5

Figure 1.5: Screenshot of the desktop when the inputfile doris02.gdf has been fed into gd1. gd1 has popped up an instance of mymtv2 that shows the generated mesh. We now have only the eighth part of the total structure.