海洋大气间气泡的气体输运

研究球形小气泡在理想流体的波浪场中的气体扩散过程，把小雷诺数下均匀来流绕流球形气泡的气体交换结果与气泡运动方程耦合在一起进行求解．讨论了溶解于水中的气体浓度、波浪、气泡半径、气泡初始深度对单个气泡气体扩散量的影响．由于气泡云对气体的输运，溶解于水中的气体可出现过饱和状态．对１０ｍ／ｓ风速下气泡云的气体输运量进行了计算，得到水中Ｏ２的过饱和度可达１．８９％～３９２％，与实际观测值一致．

GAS TRANSFER BY BUBBLES BETWEEN OCEAN AND ATMOSPHERE

The gas transfer by small bubbles in waves in the ideal fluid is studied in this paper.The motion equation coupled with the gas transfer result for the homogeneous flow over a sphericalbubble is solved. The effects of the gas concentration dissolved in the water, waves, the bubbleradius and the initial depth of bubbles on the gas diffusion of a single bubble are discussed. Therelationship between the gas diffusion from a bubble and the gas concentration in water is basicllylinear. The wave lenth has no effect on the gas transfer but the wave phase effects the initialvelocity and the rising time of a bubble directly. So, the gas exchange has the maximum at phase3n/2 and the minimum at phase n/2. As the bubble radius increases, the transfer of O2 andN2 almost grows linearly, but the transfer of CO2 raises rapidly. It maybe means that the largerbubble has much effect on the transfer of CO2. Since the bubbles located deeper have much timeto exchange the gas, the gas transfer increases linearly with the initial depth of a bubble. Somebubbles can disappear because of the exhaustion of the gas.According to Chanson's model of the bubble distribution, this paper supplies a simple modelfor personal computer to calculate the gas transfer between air-sea surface by bubble clouds. Thegas dissolved in the water can be in the supersaturation state due to the gas transfer by bubbleclouds. According to the computation of the gas transfer by bubble clouds at wind speed 10 m/s,the supersaturation of O2 in water can be 1.89% ~ 3.92%, which is consistellt with the observationsin oceans. As for large bubbles, although their number is less, their effect on the gas transfer needsto be considered seperatly because of more gas contained in one bubble.