Resistivity measurement

Administration

Person in charge:  Dipl.-Ing. Muhammad Ziauddin

Project leader:       Dr.-Ing. Sascha Heitkam

Duration:                05/2020 - 04/2023

Funding:                  DFG / Emmy-Noether

Project description

The electrical conductivity of a foam is a direct measure of the liquid content. Therefore, we use different methods to measure the conductivity of the foam with temporal and, if necessary, spatial resolution.

The simplest approach is to use pairs of electrodes that are brought into electrical contact with the foam flush with the wall. This technique is already well researched and commercialized and is reproduced by us.

Based on this, we are developing electrical impedance tomography for foams. In this medical measurement technique, several electrodes are attached to the circumference of the foam. A constant alternating current is induced between each two electrodes and the associated potentials are measured at all electrodes. From this potential distribution, the fluid distribution can be reconstructed with good temporal resolution.

Furthermore, we characterize the Wire-Mesh system of our partners from the Helmholtz-Zentrum Dresden-Rossendorf for the application in foams. This technique allows the measurement of liquid distribution with high temporal and spatial resolution. However, the wires are slightly invasive.  

Publications

Heitkam, S., and K. Eckert. "Convective instability in sheared foam." Journal of Fluid Mechanics 911 (2021).