MULTIELECTRODE CAPACITANCE SENSORS FOR THE VISUALIZATION OF TRANSIENT2-PHASE FLOWS

The use of capacitance tomography for the imaging of transient flows i n trickle-bed reactors is described. Preliminary results obtained with a 12-electrode system are displayed. The results show the possibiliti es available with capacitance tomography and allow a more detailed exa mination of the fluid dynamic effects resulting in the pursing of the cocurrent flow of gas and liquid through packed columns. To improve th e axial and spatial resolution as well as the signal-to-noise ratio of the 12-electrode sensor, a new 16-electrode sensor was developed. The improvements include the total number of electrode segments, the oper ation of the electrode segments, the axial shielding of the sensor, an d the potential of the free electrodes. (C) Elsevier Science Inc., 199 7.