Elementary study on superconducting electromagnetic ships with helical insulation wall

We, Kobe University of Mercantile Marine (KUMM) and Institute of Electrical Engineering (IEE) research teams, have carried out in Japan, the joint exp erimental test of the high magnetic held (similar to 14 T) superconducting electromagnetic ship performance in cooperation with the researchers of NRI M. In this experimental study, the major system components are thruster, se awater circulating system and various measuring instruments. The NRIMs 15 T class superconducting magnet that forms the outmost member of the 40 T cla ss hybrid magnet was used. The flow guide and flow rectifier are of same le ngths of 0.2 m, and the length of the electrodes are 0.6 m. The anode's out er diameter is 0.1 m, and the cathode's inner diameter is 0.346 m. The heli cal insulation wall is 10 mm thick and the pitch number is 3.8. During the experiment, magnetic fields were changed to six stages 3, 5, 8, 10, 12 and 14 T, whereby seawater pressures, temperatures and flow rates were measured . Electric currents were changed from 10 to 700 A. In one of results, the t hruster efficiency increases in association with the increase of the magnet ic held. It has been demonstrated that the helical-type superconducting ele ctromagnetic thruster is superior, in terms of thruster efficiency, than th at of earlier works by Iwata et al. and YAMATO-1's group. So, it is conside red that this thruster is better suited to commerical application than earl ier works. (C) 2001 Elsevier Science Ltd. All rights reserved.