Multifunctional Electrode Polarization Impedance Based Sensor for Calculating Flow Rate and Conductivity of Fluid

Abstract In this paper, we propose an equation and define the Isopotential Interface Factor (IIF) to quantify the contribution of electrode polarization impedance in two tetrapolar electrode shapes. The first tetrapolar electrode geometry shape was adjacent and the second axial concentric, both probes were made of stainless steel (AISI 304). The experiments were carried out with an impedance analyzer (Solartron 1260) using a frequency range between 0.1 Hz and 8 MHz. Based on a theoretical simplification, the experimental results show a lower value of the IIF in the axial concentric tetrapolar electrode system which caused a lower correction of interface value. The higher value of the IIF in the adjacent electrode system was KEEI (1Hz, 0.28 mS/cm) = 1.41 and decreased when the frequency and conductance were increased, whereas in the axial concentric electrode system was KEEI (1Hz, 0.28 mS/cm) = 0.08. The average isopotential interface factor throughout the whole range of conductivities and frequencies was 0.23 in the adjacent electrode system and 0.02 in the axial concentric electrode system. The index of inherent electrical anisotropy (IEA) was used to present an analysis of electrical anisotropy of biceps brachii muscle in vitro using the corrections of both tetrapolar electrode systems. A higher IEA was present in lower frequency where the variation below 1 kHz was 15 % in adjacent electrode configuration and 26 % in the axial concentric probe with respect to full range. The IIF is then shown that it can be used to describe the quality of an electrode system.

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Orthogonal Electrode Micropump Design Using DC and AC Electroosmosis

Volume 6: Fluids and Thermal Systems; Advances for Process Industries, Parts A and B ◽

10.1115/imece2011-63887 ◽

2011 ◽

Author(s):

Nazmul Islam ◽

Saief Sayed

Keyword(s):

Fluid Flow ◽

Flow Rate ◽

Velocity Measurement ◽

Impedance Analysis ◽

Electrode Pair ◽

Electrode Polarization ◽

Fluid Flow Rate ◽

Ac Electroosmosis ◽

Net Flows ◽

Capacitive Electrode

This paper investigates the micropumping action using orthogonal electrode pattern. It is reported in literature that the high microflows velocity can be achieved using orthogonal electrode pattern when excited by AC signals. Here in this paper we will investigate the effect of both AC and DC signal on orthogonal electrode pattern. We will also investigate the flow in an orthogonal electroosmotic micropump, where the combination of both DC and AC voltages were applied to optimize the fluid flow rate. The design of an orthogonal electrode pair, improves the non-uniformity in electric field, as a result producing stronger net flows at lower voltages. The capacitive electrode polarization and faradaic polarization are proposed to explain the different flow patterns. The fluid flow is explained by impedance analysis and velocity measurement. This investigation of microflow can improve the understanding of electrokinetics and hence effectively manipulate fluids.

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