Measurement and multivariate analysis of ultrasound parameters for quantitative characterization of liquids

Quantitative analysis of liquids is of interest for industrial process technology in order to assess concentrations (volume or mass fraction) of different components in mixtures (solutions, suspensions, and emulsions). The measurement of acoustic parameters of a given liquid using ultrasound is a suitable and straightforward technique for this task in many cases. In contrast, the inverse problem of quantitatively estimating the liquid's composition from the measured acoustic parameters is challenging. In this paper a methodology for multivariate analysis of parameters, selection of suitable parameters, and also for solving the inverse problem based on a parameterized analytical model is presented. The proposed concept has been evaluated by measurements with a high-frequency ultrasound (HFUS) bypass measurement cell working in the 15 to 35 MHz frequency range.