| Budget Amount *help |
¥3,500,000 (Direct Cost: ¥3,500,000)
Fiscal Year 2003: ¥1,200,000 (Direct Cost: ¥1,200,000)
Fiscal Year 2002: ¥2,300,000 (Direct Cost: ¥2,300,000)
|
|---|
| Research Abstract |
One of authors has studied new ice slurry formed by cooling water-oil mixture with stirring for ice storage system. In the system, solution of ice adhesion to cooling wall is essential. When the mixture is stirred in a vessel, oil is charged by static electricity due to friction. If the vessel wall can attract charged oil, prevention of ice adhesion to the cooling wall may be realized. At first, in order to know an amount of electrification of only oil generated by stirring, characteristics of electrification for oil were discussed. Experiments were carried out, varying the number of rotations, size of stir wing and state of ground of the vessel. Moreover, after the stop of stirring, time-dependency of amount of electrification was measured. From, experimental results, optimal conditions were clarified. And an amount of electrification became about maximum at 20~25 minutes after the beginning of stirring, and that of electrification became about 0 at 5 minutes after the stop of stirring. In order to observe behavior of charged oil-water droplet or mixture in an electric field by a high speed camera or video camera, two types of experiments were carried out. One was that oil-water droplet charged by. static electricity was made to fall plumb down between two electrodes with electric field or without electric field, varying the water content of droplet. The other was that voltage of 200 V was applied on the vessel filled with oil-water mixture of 5Qvol% oil content with stirring. From the observations, it was confirmed that attracting force between the charged wall(electrode) and charged oil acted, oil content at the wall became about 70%. Moreover, oil content at the wall could be controlled by varying the voltage. And, it was shown that this result led to prevention of ice adhesion to cooling wall.
|
