In the torsatron TJ-IU, a single coil generates the helicoidal magnetic field (l=1). The number of turns of the coil around the vacuum chamber is m=6. The vertical field is generated by a set of vertical field coils.

The TJ-IU Torsatron

The name 'TJ-IU' arises as this machine was an upgrade ('U') of the TJ-I device, in the sense that much auxiliary equipment from the latter was reused to operate TJ-IU.

Parameter Value Unit
Major radius, R0: 0.60 m
Mean plasma radius, a: 0.10 m
Minor coil radius, Rc: 0.24 m
Number of periods, m: 6
Rotational transform at the axis, ι0: 0.30
Magnetic shear: almost zero
Magnetic well depth: 6.9 %
Magnetic ripple at the axis: 7.6 %
Helical axis elongation: 0.025 m
Toroidal field, BT, at φ=30 degrees: 0.5 T
2nd harmonic Electron Cyclotron Heating, 28 - 37.5 GHz: 200 kW
The making of the TJ-IU vacuum vessel

The device was entirely built in Spain and taken into operation in 1994. In 1999, the device was sent to the University of Kiel, Germany, under a permanent loan agreement, and renamed TJ-K. Currently, TJ-K is located at the University of Stuttgart in Germany.

External links

References

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