Study on flow field in Falcon separator by high-speed dynamic photography and CFD simulation

Abstract

ABSTRACT This research builds an experimental test platform to verify practicability of theoretical calculation formula and CFD simulation (Fluent software) by comparison of measured value and calculated value, including flow film thickness, recoil water velocity, fluid velocity, and particle velocity. For liquid velocity test, 1 mm polystyrene foam beads are used as tracer particles, while solid velocity test uses fine coal with a density of 1800 kg/m3 and a particle size of 0.5 mm as observation object. Measurement results show that flow film thickness measured value is consisted of that of calculated value, all relative error is less than 5%. But increase of rotational frequency can make relative error increase slightly, this may be caused by instability of flow film due to increasing rotational frequency. In terms of recoil water velocity, its measured value is almost same as calculated value and its relative error is lower. Measurement results of fluid velocity and particle velocity indicate that variation trend of tangential and axial velocity simulation value is basically same as experimental value. However, relative error of axial tangential is greater than that of tangential by 10% for fluid velocity and relative error of axial tangential is greater than that of tangential by 20% for particle motion velocity. The large deviation of axial velocity is that direction of the axial acceleration changes easily relative to the stable tangential velocity, the “relaxation phenomenon” of tracer particles in the experiment and interference from other aspects of flow field make deviation increase slightly.