Fusion Message Board

In this space, visitors are invited to post any comments, questions, or skeptical observations about Philo T. Farnsworth's contributions to the field of Nuclear Fusion research.

Subject: Pulsing an IEC 1,2,3 BANG!!!!
Date: Oct 12, 8:37 pm
Poster: Nathan K.

On Oct 12, 8:37 pm, Nathan K. wrote:

I saw the entry on the board about Dr. Miley's work on pulsing of IEC's.
Miley's experiments on pulsing are second to none.

I can tell you that in a paper titled "Innovative Technology for an Inertial Electrostatic Confinement Fusion Propulsion Unit" there is some really good data on the pulsing method used by Miley's team."

"With pulse operation, a compact state-of-the-art pulse power supply can be employed to provide the desired kA-range peak ion currents. Because the fusion energy output scales as (I 2)-(I 3), a very large gain is obtained during the pulse. This gain is reduced by the dead time between pulses, but if a repetition rate of >100 Hz is used with a pulse width of < 1 ms, the time-average gain exceeds that obtained with steady-state operation with the same input power."

Preliminary Pulsed IEC Experiments
"The pulsed-power circuit employed in these experiments, shown in Fig. 5, was designed to provide up to 200-ma pulses with a width of tens of ms, providing a quasi-steady-state operation during the pulse. The pulse is initiated using low-level steady-state operation of the IEC, which is essential to maintain an approximately constant discharge voltage during pulse and prevent arcing when the pulse is applied. This biasing scheme allows the cathode voltage to be set to a predetermined level to establish and maintain the desired steady-state glow discharge. The resistor (R_shunt) allows a small (5-20-mA) steady-state current to flow into the cathode at all times to sustain the initial low power glow discharge. The device is then pulsed. The breakdown voltage at the device operation pressure is a few kV higher than the steady-state discharge voltage, which fallows the traditional Paschen curve."

So, I would suggest getting a copy of this and other papers that Dr. Miley has done on his IEC research at UI because they will tell you everything you need to do the pulse experiment you want to do. They will raise the reaction rate if done correctly so like all past IEC amateur experiments I suggest we revisit the safety issues once again to make sure no own gets hurt should they try these new pulse method.

Oh, notice how the biasing in the IEC is achieved for the pulsing, this was one of the issues Richard Hull brought up.

The paper that this information comes from is an AIAA paper from the 30th Joint Propulsion Conference, June 27-29, 1994, Indianapolis, IN.

Well, I hope this helps you guy's