A spatial filtering velocimeter for solid particle velocity measurement based on linear electrostatic sensor array

A novel spatial filtering velocimeter for solid particle velocity measurement in gas-solid flow system is presented based on a Linear Electrostatic Sensor Array (LESA) in the paper. The fundamental spatial filtering principle of the LESA is theoretically described, and a differential filter based on two LESAs is further proposed to remove the pedestal component of the output signal from the LESA. Thus solid particle velocity can be measured by determining the central frequency of the periodic output signal of the differential filter. A spatial filtering velocimeter consisting of a measurement head, seven-channel differential amplifiers and a computer-based data acquisition and processing system is designed and its performance is evaluated on a purpose-built gravity-fed particle flow rig and a belt rig, respectively. Experimental results show that the system repeatability is within ±5.4% over the velocity range of 1.72–3.91 m/s for a particle concentration range 0.011–0.163 m3/m3.

► A velocimeter for solid particle velocity measurement is proposed based on LESA.
► The LESA acts as a narrow-band-pass filter, and has higher spatial selectivity.
► A spatial filtering velocimeter based on LESA is designed and evaluated.
► The system repeatability is within ±5.4% over the velocity range 1.7–3.9 m/s.