Acoustic chemometrics for fluid flow quantifications—II: a small constriction will go a long way

Abstract

A new approach for non-invasive quantitative measurement of volume flow rate, multicomponent mixture concentrations as well as density and other physico-chemical intensive parameters of liquid mixtures flowing in pipelines is presented, based on novel application extensions of the well-known orifice plate principle (extensively used for flow measurement in pipes). By deliberately transgressing the conventional usage limits, the orifice plate configuration may now also be used for a range of new measurement types, all based on acoustic sensor technology. R&D has been carried out since 1987 by Sensorteknikk A/S and since 1994 in collaboration with ACRG. The acoustic chemometrics concept is characterized by easy ‘clamp-on’ deployment of acoustic sensors (primarily accelerometers), followed by an essential, integrated signal analysis/multivariate calibration data modelling, well known from chemometrics. The signal analysis step in this endeavour is often critical although rarely outside conventional electrical engineering scopes. We present three fluid/fluid or fluid/solid mixture application type cases: (1) trace oil-in-water determination (representing one-analyte systems); (2) jet-fuel/glycol mixture determination (representing two-analyte systems); (3) paper-pulp constituent(s) determination (representing analyte–interferents systems). We also describe extension studies of these first quantitative acoustic chemometrics forays, e.g. for alternative measurement of (conventional) flow velocities of both fluid/fluid and fluid/solid (slurries) systems (average volume flow rate of heterogeneous multiphase systems), for flow regime characterization and for measurement of the effective in-line density of (fluid/fluid and fluid/solid) mixtures. There would appear to be a vast potential for technological and industrial applications of this new type of acoustic chemometric process and product characterization/monitoring. Copyright © 1999 John Wiley & Sons, Ltd.