2013-04-20 14:05:16 UTC
winding then the current sheet is 800 A so the plasma curent is 800 A.
The plasma is generated by the ionisation wire which is excited by 20KV
60KHz power supply.
The ion pressure is 800.800.mu/D/length of winding. But since the
current is actually a standing wave them there is a maximum current in
the middle and zero at the ends making the pressure a bit quite a bit
bigger near the middle. The pressure I calculated as about 10^8Pa and
the plasma heats by ohmic heating with the maximun near the middle and
near the axis. When the temperature reaches 6KeV (that is about 10^11 K
the power reaches its maximum. This is only near the middle and near the
axis the insulation is because the ionised gas does not diffuse outward
because of the ion pressuree and is kept near the maximum because it is
the maximum current. The fusion reactions futher heat the gas and the
ions exert pressure on the containment current this inducing more
current in the winding. The current density near the centre is very high
because the area over which it flowes is about 1mmx6mm so the current
density is 800/6E-6 or 8E8A/meter^2.
The copper loss is the resisance of the winding (2000Ohm) and the
current (40mA) which is 80 Watt.
The power generated is 0.5 Watt/cc/kPa^2 and with a reaction volume of
18E-2 so the power is 18E-2x0.5x(10E8/1000)^2 or 9E10Watt (90GW). It
cannot be run at that power because the current generated is too high
for the windings and since this extra current increasss the pressure the
power simply rises exponentially until the unit explodes.
THe power is controlled by the shunt regulator by shunting the windings
when the potential rises to the preset level.
To make a high power unit the reaction chamber remains the same but the
resonance winding is made of insulated copper tube of the same
inductance. This will have a smaller number of turns because the winding
has a bigger diameter. I do not know how to work the inductance out from
the number of turns and dimensions of the winding. You can estimate from
the gaussian formula for a single turn coil and after winding, measure
the inductance. Then calculate the capacitance for resonance at 50 Hz.
Calculate the potential reached at maximum power to estimate the voltage
rating of the capacitor and similarly the current rating. To get 50KW at
400 V the current output will be 125A. So the tank circuit must run at
about 1250A so only 10% is taken to load. The output winding will have
about 400T of 125A wire with the output voltage of 400 volt. To
calculate the potential across the tank circuit the turns of the
resonance winding need be known. So build the resonace cicuit first and
then find the potential it develops at low power (the exciter across the
resonance coil) and then measure work out the turns for the output
To reduce the copper loss and cool the winding the copper tube winding
needs liquid nitrogen flowing in the tube.