Measurement of Velocity and Concentration Profiles of Pneumatically Conveyed Particles Using an Electrostatic Sensor Array

The ability to monitor the velocity and concentration profiles for the whole diameter of a pipe would allow the complex flow dynamics associated with particles in a pneumatic suspension to be measured. This paper presents a method of online monitoring of the particle velocity and particle concentration for the whole diameter of the pipe for a pneumatic bulk solid conveying system. This is achieved using an array structure of five electrostatic sensors across the whole diameter of the pipe to measure the particle velocity and concentration profiles. Experimental tests were carried out on a laboratory-scale test rig over a range of particle velocities. The results show that the electrostatic sensor array is capable of measuring the multiple velocities and concentrations that occur across the diameter of a pneumatic conveying pipe. Through the analysis of velocity and correlation coefficient data, flow across the diameter of the pipe including that along the pipe wall is determined to have more turbulence than the flow at the center of the pipe.