Change-point-detection-based method for solid velocity measurement using twin-plane electrical capacitance tomography

This paper proposes a novel method for flow velocity measurement in twin-plane electrical capacitance tomography (ECT) system, and applies it to coal ash measurement in a pneumatic pipeline. The proposed method is base on the Mann-Kendall method, which has been frequently used in abrupt climate change detection. First, the change-point of cross-sectional solid concentration values at each plane is detected separately using the M-K method; thereafter the transit time can be estimated as the difference between the change-points detected at the upstream and downstream planes. The change-point-detection-based method has released the basic assumption required by the classical cross-correlation method, and thus can increase the scope of velocity measurements. Experimental results indicate that the ECT system is capable of detecting various velocity profiles and solids distributions, which can be useful for the monitoring and predicting of flow instability and solid blockages.