EXPERIMENTAL INVESTIGATION ON SOUND SPEED PROPAGATING THROUGH HIGH SPEED AERATED FLOW IN OPEN CHANNEL

摘要

An experiment concerning the sound propaga- tion in aerated open channel flow was designed and conducted in a variable slope chute. The acquisition of sound data was done by the hydro-phones installed into the bottom wall of the chute. The data were analyzed and processed by the tape re- corder and a 3562A analyzer. The primary experimental results indicated that the sound speed in aerated flow is varied with the air concentration and highly lower than each of the sound speed I pure water or air. As released by the derived theory formula, the minimum sound of 24m/s in aerated flow hap- pened when the air concentration achieved to 50/100. This result shows that the compressibility of high speed aerated flow should be considered when the air concentration is near to 50/100. A criterion of compressibility of high speed aerated flow was also given in this paper.