The presence of air in a water pipeline may seriously affect the operation of such a pipeline, the most significant effect being the increase in friction head loss. The authors enumerate the various problems that have been encountered with air entrainment, discuss some of the previously proposed solutions, and summarize some of the more important research findings in this field.
Use was made of a laboratory pipeline model to study and quantify the effect of air entrainment on head loss. The experimental results were compared with an equation derived for the prediction of head loss, and found to agree.
Feedback from experience is essential because engineering is still basically empirical. Failures continue to occur. No one has the same understanding of a structure as its designer, and he should maintain long-term contact with it. When the designer dies, it is not fanciful to say that something is lost to the structure.
The continuing Education Liaison Committee has compiled the following list of courses and symposia scheduled for the remainder of 1983. It is the intention to update this programme regularly and to include activities such as courses, site visits and symposia which are of interest to members.