Characterization of the velocity and concentration of pneumatically conveyed particles in the upstream of an acoustic emission waveguide through CFD-DEM modelling and electrostatic sensing

Characterization of the velocity and concentration of pneumatically conveyed particles in the upstream of the waveguide protruded into the flow is essential for measuring the mass flow rate and size distribution of particles using acoustic emission methods. Computational fluid dynamics-discrete element method (CFD-DEM) is employed in this paper to simulate the collisions between particles and waveguides with a varying protrusion depth in a vertical pipe. Then an instrumentation system incorporating electrostatic sensors is developed to measure the particle velocity and concentration in the upstream of the waveguide. Experimental tests were carried out on a particle flow test rig. The experimental and modelling results show that the waveguide protruded into the flow between 2 and 10 mm results in a reduction in particle velocity of approximately 30%–35 %, and an increase in particle concentration of approximately 3%–20 %. The experimental results show a close agreement with the modelling data.