Thermal Study of Electrodes BeginsMarch 29, 2018
The cooling of the plasma focus electrodes, especially the anode, is likely to be the toughest engineering problem to be faced in going from a demonstration of net fusion energy in the lab to a working fusion generator. To get a head start on the problem LPPFusion investor Jerry Black has teamed up with fellow engineers John Blanton and Mike Ruthemeyer to simulate the heating process. The team met while they were all working on the design of giant General Electric turbines. Initial studies (Figure 3) indicate that, as the LPPFusion research team anticipated, the greatest heating will come from the X-rays emitted by the plasmoid. These studies also confirm the vast superiority of beryllium, which minimally absorbs X-rays, therefore minimizing electrode heating. Further studies will make the X-ray emission spectrum and the distribution of current in the electrodes more realistic. Such studies will speed up the engineering phase once the research phase is complete. Thanks to Jerry for organizing—and funding—this effort!
Figure 3. An initial simulation of heating of the electrodes by a single pulse of the FF-1 device. Redder colors indicate hotter regions. As can be seen, the tip of the anode (inner cylinder) receives the most heating from the plasmoid’s X-rays, which also penetrate deeply into the rest of the anode and the cathode (middle cylinder). The walls of the chamber (outer cylinder) remain cool.