Talk Polywell and IECFusiontech have uncovered details of the WB-8 contract [pdf]. Those details can give us some insight into how WB-7 has gone.
The WB8 design shall use circular coils around each main face cusp axis. The device shall use emitter electron gun arrays and an ion beam drive. The machine will be operated in magnetic fields with pulsed currents. WB8 shall be operated at a magnetic field strength of approximately 0.8 Tesla, which represents an increase of 8 times the magnetic field strength of previous WB machines. Improvements over previous WB machines in WB confinement, ion energy and fusion reactivity are expected as a result of these changes to WB machine design.
AS M Simon explains
An increase of field strength by a factor of 8 means - if the scaling laws hold a factor of about 4,000 increase in power out. If WB-7 was similar to WB-6 it means an increase from 3 neutrons a shot to 12,000. A real countable number i.e the error bars will be much lower. A count of 3 can actually be considered a count of 3 +/-2. That is a big error bar. For 12,000 the error bar is on the order of +/-100 about 1%. That makes improvements or degradations of 5% easily detectable. Where as in the first situation (WB-6/7) changes that doubled or halved the output rate would be hard to detect.
WB 8.1 : Testing Aneutronic proton/boron 11
Enhanced Ion Drive with PB11 (proton/boron 11): Based on the results of WB8 testing, and the availability of government funds the contractor shall develop a WB machine (WB8.1) which incorporates the knowledge and improvements gained in WB8. It is expected that higher ion drive capabilities will be added, and that a “PB11” reaction will be demonstrated. The contractor shall investigate and validate the plasma scaling laws with respect to B-field, voltage and reactor size. The contractor shall investigate the feasibility of a neutron-free fusion power reaction using a polywell WB machine. It is anticipated that improvements in WB confinement, ion energy, and fusion reactivity will be demonstrated in WB8.1. Improvements over the WB8 predictive, computational model are expected, which should yield a better understanding of the WB fusion reaction thus allowing optimization of the WB machine.
The contractor shall deliver a report detailing the results of the experimental testing of WB8.1. The report shall address the conceptual requirements for a polywell fusion reactor capable of generating approximately 100 milliwatts.
From M Simon:
At 100 milliwatts for a follow on reactor they are starting to get into the power range. If they can get that kind of power with .3 m diameter. coils and .8 T fields, then a reactor with 3 m coils and 10 T fields should produce about 2.5 Mega Watts if the scaling laws hold.
WB-9 Follow-Up Discussion
The contractor shall deliver a conceptual design for a follow-on fusion demonstration device, WB-9. Conceptual studies will focus on the feasibility of extending the WB-8 results to this device and determining the suitability of this concept as a fusion reactor.
AGEE refers to Advanced Gaseous Electrostatic Energy (AGEE).
Talk Polywell discussion on these documents