Figure 1 shows the full geometry imported into CST EMS which consists of an anode and cathode system, a lead shield, and a metallic housing. These components contain a lot of rounded and sharp edges which affect the eletcric field distribition.
The main goal of the simulation is to determine the maximum field strength in the model. The design of the housing for the X-Ray tube can then be optimised to reduce the potential of arcing. Results may be post-processed in terms of field values at specific points, along curves or on material surfaces.
Figure 2 shows the applied source potentials which include the 0V for the housing and cathode (blue), 90 KV to the anode and anode base(red). The lead ring (green) is set to 45KV....
The simulation takes about 4 minutes on a Pentium IV machine and delivers primary quantities such as the electric potential shown in figure 3.
In addition to the potential, the electric field values can also be plotted in vector form as shown in figure 4. The field was plotted on a central cut-plane using a logarithmic scaling to aid visualisation. Maximum field values in the model may be extracted automatically in the post-processor.