Dual sensor for simultaneous measurement of electrical impedance and temperature during ice formation process

Impedance spectroscopy is often applied to characterize solids and fluids since each substance presents its own and sometimes unique impedance spectra. In industrial applications, impedance spectroscopy has the potential to monitor many processes such as those occurring in chemical reactors or liquid transportation in pipelines. In this paper, we introduce a sensor being able to perform measurements of impedance spectra (from few Hz to few MHz) allied to precise temperature measurements based on optical fiber Bragg grating sensors which was applied for monitoring ice formation, as exemplary process. The new sensor is described, calibrated and tested. The system was evaluated by measurements with known substances. Ice formation process was monitored and some findings are presented and discussed.