Water flow generation owing to interaction between pulsing bubble and rigid wall

Abstract

Generating a directed water flow in periodic forming a non-symmetrical acoustic field was experimentally investigated in the work. Periodic acoustic wave field was formed with the help of a vapor-gas bubble pulsing in the hole of a thin diaphragm near a rigid wall. Alternate formation of two water flows moving in opposite directions was found. During the bubble growth stage the flow at velocity V1 was formed in the opposite direction of the plate, and during the bubble collapse stage the flow at velocity V2 was formed towards the plate. By changing the parameter k=R/r where R was a distance from the hole center to the rigid wall, and r was a hole radius, the possibility to control average values V1 and V2 was shown. It was found that at k=R/r=5.8 V1=V2, at k>5.8 V1>V2, and at k<5.8 V1 was less than V2. It was shown that due to variation of the distance between a pulsing bubble and a rigid wall it was possible to control velocity V and direction of the total flow of water through the hole. The maximum value of velocity V reached 40 cm/s in the experiment.