論文
油中の電場付与用電極板と衝突する過冷却水滴の凍結開始
－電極板材質の影響－
キーワード:
Freezing,
Supercooling,
Electric field,
Thermal storage,
Direct-contact heat transfer,
Water droplet
2013 年 30 巻 3 号 p. 265-275
詳細
2013 年 30 巻 3 号 p. 265-275
A charged water droplet in oil with electric field, which formed between two plate electrodes, is forced to collide alternately with each electrode. This collision has the possibility of offering the effect of freezing initiation of super cooled water droplet, if the temperature of the system is below the freezing point of water. The initiation may be affected by the material of the electrodes.In this paper, copper, nickel, stainless steel, aluminum, and gold-plated plates were used as the electrodes. The supercooling degree and the electric field strength are varied in the experiment.For aluminum and gold-plated electrodes, the more reciprocation did not continue due to the adhesion of the water droplets to the electrode. In case of 0.160 MV/m in electric field strength, the droplets of 47% adhered in case of stainless steel and 38% in nickel, though the adhesion to copper was hardly seen. In case of supercooling degree of 4 K, each material also showed the effect of initiation of freezing, except aluminum and gold plated electrodes. The electric field strength necessary for the initiation for all droplets was 0.192 MV/m in case of nickel and stainless steel, and 0.224 MV/m in copper, at – 4℃ in oil temperature.
