An acoustic technique for bubble size measurement in bioreactors

An idealised model for the production of sound due to bubble formation is used to demonstrate a technique to estimate the bubble size distribution from a sound spectrum (sound pressure-frequency trace). It is assumed that when a bubble is formed it emits a damped, sinusoidal pressure pulse at its natural frequency and that the overall sound produced is due to the summation of the various pulses. This technique could be used for determining gas-liquid interfacial area where other methods are inappropriate and inaccurate in mass transfer studies. The potential advantages of using acoustics are that it could be used on-line and in opaque liquids.