Planar Array Sensor for High-speed Component Distribution Imaging in Fluid Flow Applications

• Published in: Sensors (Basel, Switzerland) Vol. 7; no. 10; pp. 2430 - 2445
• Main Authors: Da Silva, Marco Jose, Sühnel, Tobias, Schleicher, Eckhard, Vaibar, Roman, Lucas, Dirk, Hampel, Uwe
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 19-10-2007; Molecular Diversity Preservation International (MDPI)
• Subjects: Accuracy; Dielectric properties; Electrodes; Electronics; flow imaging; Full Research Paper; interdigital electrode; multicomponent flow; multiphase flow; Nondestructive testing; phase distribution; planar sensor; Printed circuit boards; Sensors; Transmitters; flow imaging; interdigital electrode; multiphase flow; multicomponent flow; phase distribution; planar sensor
• ISSN: 1424-8220; 1424-8220
• DOI: 10.3390/s7102430

A novel planar array sensor based on electrical conductivity measurements ispresented which may be applied to visualize surface fluid distributions. The sensor ismanufactured using printed-circuit board fabrication technology and comprises of 64 x 64interdigital sensing structures. An associated electronics measures the electricalconductivity of the fluid over each individual sensing structure in a multiplexed manner byapplying a bipolar excitation voltage and by measuring the electrical current flowing from adriver electrode to a sensing electrode. After interrogating all sensing structures, a two-dimensional image of the conductivity distribution over a surface is obtained which in turnrepresents fluid distributions over sensor's surface. The employed electronics can acquire upto 2500 frames per second thus being able to monitor fast transient phenomena. The systemhas been evaluated regarding measurement accuracy and depth sensitivity. Furthermore, theapplication of the sensor in the investigation of two different flow applications is presented.