A high frequency electronic transducer for multiphase flow measurements

This paper describes an electronic transducer for multiphase flow measurement. Its high sensitivity, good signal to noise ratio and accuracy are achieved through an electrical impedance sensor with a special guard technique. The transducer consists of a wide bandwidth and high slew rate differentiator where the lead inductance and stray capacitance effects are compensated. The sensor edge effect is eliminated by using a guard electrode based on the virtual ground potential of the operational amplifier. A theoretical modeling and a calibration method are also presented. The results obtained seem to confirm the validity of the proposed technique.

[1]  Maurice Beck,et al.  Design of sensor electronics for electrical capacitance tomography , 1992 .

[2]  W. Heerens.  Application of capacitance techniques in sensor design , 1986 .

[3]  Maurice Beck,et al.  Tomographic imaging of two-component flow using capacitance sensors , 1989 .

[4]  M. S. Beck,et al.  8-electrode capacitance system for two-component flow identification. II. Flow regime identification , 1989 .

[5]  D. A. Meneley,et al.  Single-exposure neutron tomography of two-phase flow , 1986 .

[6]  D. A. G. Bruggeman.  Berechnung verschiedener physikalischer Konstanten von heterogenen Substanzen. I. Dielektrizitätskonstanten und Leitfähigkeiten der Mischkörper aus isotropen Substanzen , 1935 .

[7]  Tomasz Dyakowski,et al.  Industrial application of electrical tomography to conveying processes , 1993 .

[8]  M. S. Beck,et al.  8-electrode capacitance system for two-component flow identification. I. Tomographic flow imaging , 1989 .

[9]  F. Walz.  An Ultra-Compact LC-Oscillator for the Study of Lattice Defects in Magnetic Materials , 1995 .

[10]  Paolo Andreussi,et al.  An impedance method for the measurement of liquid hold-up in two-phase flow , 1988 .

[11]  Richard A Williams,et al.  Process tomography for identification, design and measurement in industrial systems , 1992 .

[12]  Brian S. Hoyle,et al.  Electrical capacitance tomography for flow imaging: system model for development of image reconstruction algorithms and design of primary sensors , 1992 .

[13]  S. Torquato,et al.  Determination of the effective conductivity of heterogeneous media by Brownian motion simulation , 1990 .

[14]  Maurice Beck,et al.  REVIEW ARTICLE: Electronic transducers for industrial measurement of low value capacitances , 1988 .

[15]  J. Carru,et al.  A measuring device for the determination of the electric permittivity of materials in the frequency range 0.1-300 MHz , 1982 .

[16]  Maurice Beck,et al.  Flow imaging for multi-component flow measurement , 1987 .

[17]  S. L. Wellington,et al.  Tomographic imaging of three‐phase flow experiments , 1987 .

[18]  J. C. Borst,et al.  A CAPACITANCE SENSOR FOR TWO-PHASE VOID FRACTION MEASUREMENT AND FLOW PATTERN IDENTIFICATION , 1988 .

[19]  M W E Coney,et al.  The theory and application of conductance probes for the measurement of liquid film thickness in two-phase flow , 1973 .

[20]  R G Green,et al.  A new capacitance transducer for industrial applications , 1988 .

[21]  G. E. Fasching,et al.  A capacitive system for three‐dimensional imaging of fluidized beds , 1991 .

[22]  F. J. Dickin,et al.  Tomographic imaging of industrial process equipment : techniques and applications , 1992 .