Breaking of Ice Using Pulsed Power

摘要

Summary form only given. Recently, the traffic on icebound sea tends to be important for development of natural resources production. For example, in the Northern Sakhalin offshore of Sea of Okhotsk, located to the north of Hokkaido, Japan, commercial production of crude oil and gas started. At the present the productions in the winter season are not carried out. The year-round productions, including the winter season, at which Sea of Okhotsk is covered by sea ice, are planed. In this research, breaking of ice sheet by shock wave produced by pulsed power generator is proposed as a new method for operation of icebreakers in order to realize safe and quick navigation at the icebound sea. The shock wave can be produced by discharge formation between the electrodes contacted to ice sheet. In the experiments carried out as a preliminary testing, the breaking of ice was confirmed. The voltage of 48 kV was applied using a pulsed power generator and the maximum discharge current of about 1.5 kA flowed through the discharge pass. The discharge started at about 30 ms after applying the voltage. At that time the maximum discharge power of about 40 MW and the discharge energy of about 33 J were obtained. Furthermore, experiments in which the thickness of ice was changed, were curried out. According to these experiments, the total energy of about 1000 J was required at 100 mm of ice thickness for destruction of ice