HWAHAK KONGHAK, Vol.23, No.3, 179-187, June, 1985
두 액상 계면을 이용한 단일기포의 drift에 관한 연구
A Study on the Drift behind Single Air Bubble Using Two Liquids-Interfaces
초록
단일 기포의 drift에 관한 연구를 위해서, 서로 불용인 두 액상계면을 만들고, 기포가 이 계면을 통과할 때의 계면 변화를 조사하였다. 상층액에서의 기포 장축을 기준으로한 drift profile은 상-하층액의 비중 및 점도가 모두 같은 경우를 제외하고는, 기포 장축의 영향을 받았다. 그러나, 하층액의 점도가 상층액의 점도와 같거나 큰 계에서 하층액에서의 기포 장축을 기준으로 한 drift profile은 기포 장축이나 상층액의 물성치에 무관하게 일정하며, 하층액의 점도가 감소함에 따라 감소하여, 결국 Darwin의 total drift에 접근한다. Drift가 기포 장축의 영향을 받지 않는 각 계의 평균 drift를 하층액의 점도와 연관지어 다음과 같은 식을 얻었다.
1/S-1.11 = 0.1+0.2μl-1+0.05μl-2
이 식에서 점도를 영（zero）으로 외삽한 값은 1.11로써 Darwin의 total drift에서 구한 drift area 0.95와 큰 차이가 없다.
1/S-1.11 = 0.1+0.2μl-1+0.05μl-2
이 식에서 점도를 영（zero）으로 외삽한 값은 1.11로써 Darwin의 total drift에서 구한 drift area 0.95와 큰 차이가 없다.
For investigation of the drift behaviors behind single air bubble, interfaces between two insoluble liquids were introduced. In this system, the shape variation of the interface was clearly observed when a bubble was passing through the interface. A dritf profile based on the major axis of the bubble in the upper phase of the solution is influenced by the bubble size.
For each system whose viscosity of the lower phase is as large as or larger than that of the upper phase, the drift profile based on the major axis of the bubble in the lower phase is nearly independent of both the bubble size and the physical properties of the upper phase of the solution. The averaged drift in this experiment decreases with the decrease of the viscosity of the lower phase and ultimately approaches Darwin's total drift. To examine the coincidence between Darwin's total drift and data obtained in this work, the averaged drift area of each system was correlated to the viscosity of the lower phase. The correlation shows as follows.
1/S-1.11 = 0.1+0.2μl-1+0.05μl-2
The drift area extrapolated to that of zero viscosity was 1.11, and this value is nearly coincident with that of Darwin's total drift area, 0.95.
For each system whose viscosity of the lower phase is as large as or larger than that of the upper phase, the drift profile based on the major axis of the bubble in the lower phase is nearly independent of both the bubble size and the physical properties of the upper phase of the solution. The averaged drift in this experiment decreases with the decrease of the viscosity of the lower phase and ultimately approaches Darwin's total drift. To examine the coincidence between Darwin's total drift and data obtained in this work, the averaged drift area of each system was correlated to the viscosity of the lower phase. The correlation shows as follows.
1/S-1.11 = 0.1+0.2μl-1+0.05μl-2
The drift area extrapolated to that of zero viscosity was 1.11, and this value is nearly coincident with that of Darwin's total drift area, 0.95.