Acoustic Characterization of Fluorinert FC-43 Liquid with Helium Gas Bubbles: Numerical Experiments

Abstract

In this work, we define the acoustic characteristics of a biphasic fluid consisting of static helium gas bubbles in liquid Fluorinert FC-43 and study the propagation of ultrasound of finite amplitudes in this medium. Very low sound speed and high sound attenuation are found, in addition to a particularly high acoustic nonlinear parameter. This result suggests the possibility of using this medium as a nonlinear enhancer in various applications. In particular, parametric generation of low ultrasonic frequencies is studied in a resonator cavity as a function of driving pressure showing high conversion efficiency. This work suggests that this medium could be used for applications such as parametric arrays, nondestructive testing, diagnostic medicine, sonochemistry, underwater acoustics, and ultrasonic imaging and to boost the shock formation in fluids.

Modeling and Simulation of Parametric Nonlinear Focused Ultrasound in Three-Dimensional Bubbly Liquids with Axial Symmetry by a Finite-Element Model

“…Its sound speed, nonlinear parameter, and attenuation coefcient can be raised over determined frequency bands. Tis characteristic greatly afects the propagation of ultrasound [4][5][6][7]. In this paper, we study ultrasound of fnite amplitude that focuses on a bubbly liquid by means of a numerical model.…”

“…Others study the behavior of the focus by taking the dispersion of a medium (not due to gas bubbles) into account through the resolution of KZK-based equations [25,26]. It is worth noting that [25] shows the focus shift when dispersion is considered, but with a low coefcient of nonlinearity compared to a bubbly liquid, which is several orders of magnitude higher than the corresponding homogeneous liquid [5]. Other works study one-dimensional bubbly cavitating fows in elastic fuids, such as [27], which models this phenomenon through microsized nozzles of diferent shapes.…”

Linear Iterative Procedure to Solve a Rayleigh–Plesset Equation

“…This model equation was derived in 1973 by Zabolotskaya et al [3]. It was used in conjunction with the wave equation to analyze effects caused by a population of gas bubbles in a liquid, which parameter of nonlinearity increases by several orders of magnitude, on an ultrasonic field through the development of second-order perturbation methods [3,4] and numerical models [5][6][7][8].…”