Experimental Study of Granular Material Flowability in a Heat Exchanger

This paper presents an experimental investigation of granular material flowability in a heat exchanger. Spherical silicon particles are used as the granular materials in this study. The velocity profile created shows uneven particle velocity where particles towards the outlet flow faster with the velocity reaching 9.09 mm/s and the particles close to the wall flow slower with the velocity reaching 1.63 mm/s. Compared to the Carr classification of flowability proposed in the literature, the angle of repose obtained through the experiment, which is 15°, suggests that the particles are very free flowing. This is supported by the coefficient of rolling resistance which has been obtained as 0.001, suggesting that these particles have a lower rolling friction resistance, leading to a more efficient movement. Moreover, the mass flowrate implies that 140.85 grams of particles flow out per second. These findings suggest that particle size, outlet size, friction factors and the space between the heating elements and the walls affect the flowability of particles in the heat exchanger.