A conceptual design of bubbles rising in the water

Air-lift artificial upwelling for deep ocean water efficiency is simulated with a simplified computational model of two-phase flow in an upward pipe. The model is simulated in the two-dimensional space and based on the momentum transfer between the two phases. The influence of the pipe diameter and length on the lifting efficiency has been investigated numerically. It was shown that the increase of the pipe diameter led to the increase of the lifting efficiency. However, with the increase of the pipe length, the lifting efficiency of the liquid was reduced slightly. The simulating results indicated that the parameter of the pipe diameter is more sensitive than the pipe length. In addition, increasing the pipe length also led to the reduction of the lifting efficiency due to the wall friction in a stable full-blown flow field.