Investigation on the Flow Characteristics of the Bottom Aerators on the Chute with a Circular Arc Section

The chute bottom aerator is often used to protect discharge works against cavitation erosion caused by high velocity flows and it has become more and more popular as it has been proved to be an economical, effective and successful measure by many hydraulic projects. The flow characteristics of an aerator inserted on the chute with a circular arc section is more complex than that of on the chute with a straight segment. The area of the air intake of the aerator, the air pressure in the cavity after the aerator and the backwater in the cavity are very important factors which influence the flow aeration effects for the aeration facilities. How these factors affect flow characteristics is investigated by theoretical analysis and systematic model tests. The results show that the cavity length increases with the increasing of the air intake area at first, and then it remains unchangeable for a discharge even though the air intake area continues to increase. But the air pressure in the cavity decreases with the increasing of the air intake area. Some factors, such as flow discharge, aerator style, the cavity air pressure which influence the backwater in the cavity are investigated.