Microwave Velocimeter Based on Cross-Correlation for Dual-Phase Flows

Accurate velocity measurement of solid particulates in multi-phase flows is critical for many industrial processes. This paper presents a non-intrusive microwave velocimeter for solid particulates in gas/solid flows. The proposed velocimeter is founded upon the cross-correlation principle while operating at 24 GHz. By having two sensors 5 cm apart, the velocity of the particulates is deduced from the relative delay in the reflected waves received by both sensors. The deployed sensor is a hermetically sealed circular waveguide with a custom-made TEM-to-TE11 mode transition. The proposed system is tested experimentally on a 1 inch PVC process pipe. The measurements drawn from the proposed system are benchmarked against a high-speed camera measurements acquired downstream of the microwave velocimeter. Experimental results demonstrate a promising performance that can be further enhanced for real-time velocity measurement in industrial processes.