Validation of flow following sensor particles with ERT in a stirred vessel

Validation of flow following sensor particleswas conducted using ERT in a stirred vessel (volume ≈ 80 L) of non-NEWTONIAN liquid. The particles give a significant contrast in the ERT images (5% of signal variation) and thus can be easily detected. Average fluid circulation timeswere estimated from (i) the measured vertical position of the sensor particle, (ii) the fluctuating ERT signals ofsingle ERT-planes and (iii) the measured mixing times of ERT-NaCl-tracer experiments. The estimated average circulation times of all the three methods are comparable for the two investigated impeller positions. The excellent detectability of the particles and the consistent results confirm the feasibility of the ERT method for further validation of flow following sensor particles in stirred vessels.