LEVITATION COIL TESTS

We are readying the facility for a full integration test of the levitation systems. The levitation coil will operate in conjunction with the floating coil. Strain gauges installed in the launcher will measure the decrease in weight of the floating coil as the levitation coil in excited so as to permit a final calibration of the currents and resulting forces between the floating and levitation coils.

During plasma shots noise is present and is picked up by diagnostics including the laser occlusion system that locates the floating coil during levitation. It is important that plasma generated noise does not affect the laser based control system and we will measure the level of noise observed in the laser system during plasma experiments.

Fig. 1 Floating coil showing striped occultation band. The band serves to occult laser lines for determining the vertical and horizontal location of the coil. Stripes indicate coil rotation. Also seen is the upper launcher structure, designed to prevent upward motion in the event of loss-of-control event. The three tubes containing new flux loops are also seen in the picture (indicated by arrows).

Fig 2. A laser line is seen reflecting from the occultation band.

LEVITATION SYSTEMS: CATCHER/LAUNCHER

The launcher-catcher is being manufactured by Hollis Machine.

NEW DIAGNOSTICS

The planned campaign will provide the first test of a 4 channel microwave interferometer array. New flux loops (Fig. 1) are mounted on the upper launcher structure.

RECENT PUBLICATIONS

A. Zhukovsky, D.T. Garnier, V. Fishman, R. Lations, "Retractable Helium Transfer Lines for the Floating Fusion Magnet", International Cryogenic Engineering Conference 21 in Prague (CryoPrague 2006) July 17-21 (2006).

Zhukovsky A., Michael P.C., Schultz J.H., Smith B.A., Minervini J.V., Kesner J., Radovinsky A., Garnier D., Mauel M., First integrated test of the superconducting magnet system for the Levitated Dipole Experiment (LDX), Fusion Engineering and Design, (2005), 75-79, Part B, 29-32

Zhukovsky A., Garnier D.T., Radovinsky A., Thermal performance of the LDX F-coil, Adv. in Cryo. Eng., (2006), 51, 78-85.

Zhukovsky A., Garnier D.T., Operation of the Levitated Dipole Experiment floating coil, IEEE Trans. App. Superconductivity, (2006), 16, 898-901.