The short and less technical version from Classical Values.
1. The machine is working way better than the usual theories predict
2. No one knows why (lots of suspicions floating around)
3. New instruments are being added
4. The current machine is called WB-7. WB 7.1 (no details) is in progress.
The technical version mainly in Dr. Nebel's, project leader of the IEC Fusion project words:
Here’s what we know and what we don’t know:
1. We don’t have the spatial resolution of the density to see if the cusps are quasi-neutral [quasi-neutral means the plasma has roughly the same number of positive ions and negative electrons] on the WB-7
2. In one-D simulations the plasma edge (which corresponds to the cusp regions) is not quasi-neutral. Therefore, if the cusps [ a “cusp” is where the confining magnetic fields meet, in this case four fields meeting at a point at each corner of the cube the coils approximately] are quasi-neutral it must be a multidimensional effect.
3. Energy confinement on the WB-7 exceeds the classical predictions (wiffleball based on the electron gyro-radius) by a large factor. [The test machine is kicking the butt of earlier versions of machines of this type]
Our conclusion is that both the wiffleball and the cusp recycle are working at a reasonable level.
Polywells are run slightly electron-rich to confine and focus the ions, so they are not ambipolar and thus the area on the edge of the plasma is expected to have many more electrons than ions. Points 1 and 2 are important because significant numbers of ions in the cusps probably doom the concept in terms of achieving commercializable energy generation from fusion.
However, vastly superior numbers of fusions could still be leveraged this fusion device as a neutron generation source for uses such as transmutation. There have been proposed fusion/fission hybrids where the performance of the nuclear fusion part is ten to forty times less than that of pure energy generation fusion.
Plasma potentials at wikipedia
Talk Polywell discussion forum where Dr. Nebel is leaving some remarks and occasionally debating with Art Carlson.