Increasing the gas dissolution rate of bubbles via a non-invasive resonant acoustic technique

Abstract

An acoustic technique designed to increase the gas-dissolution rate of a bubble in a liquid medium is here presented. The increased gas-dissolution rate is achieved by increasing the bubble’s surface-to-volume ratio via bubble fragmentation. This was accomplished by attaching an electroacoustic transducer to the system or load in which bubbles travel and exciting the transducer at the frequency of resonance. We have demonstrated that the electric resonance of the transducer attached to the system corresponds in frequency to the mechanical resonance which allows for achieving such a state without the use of an internally placed hydrophone to certify the resonance state. The acoustic bubble fragmentation technique proved to be able to increase the dissolution rate 4 to 5 times of bubbles with initial diameters between 150 and 550 µm in distilled water and in medical grade saline solution. Possible mechanisms responsible for the results obtained are discussed as well as additional advantages of the technique. The technique has potential medical applications such as an on-site emergency treatment for scuba divers suspected to be at risk of developing decompression sickness and in any other clinical scenario where the risk of an air embolism might be present.