Towards nonlinear ultrasonic characterization of air microbubbles in water

International audienceThe characterization of argon microbubbles in liquid sodium is currently being investigated in connection with the development of Generation IV nuclear reactors. It seems that nonlinear acoustic techniques can be used to determine the void fraction (volumetric fraction of free gas) and the histogram of the bubble radii. We discuss the first stage of our workhere: the development of an experimental test bench suitable for generating air microbubbles in water and then measuringthem optically, before attempting an acoustic characterization. The bubble clouds generated have a radius distributioncentred on about 20 microns