Effect of inlet periodic velocity on the performance of standard cyclone separators

In some engineering applications, the inlet velocity of cyclones for gas-solid separation varies periodically with time. This investigation is based on a push chain concrete spraying machine, measures and trigonometrically characterises the inlet periodic air velocity. Four standard cyclones and a design cyclone have been simulated to investigate performance under inlet periodic velocity. The simulation of the particle and fluid phases of the cyclone was carried out using the Reynolds Stress Model (RSM) using Computational Fluid Dynamics (CFD). The designed cyclone was used to verify the simulation results, the simulation and experimental data were in good agreement. The results of the study show that the 1D3D/w cyclone is optimal for the gas-solid separation of push chain concrete spraying machine. The effect of cyclone inlet size on separation performance under periodic velocity is significant. Furthermore, the concept of hysteresis time is defined by the difference between the time corresponding to the peak number of escaped particles and the time corresponding to the inlet velocity peak. Inlet periodic velocity can lead to situations where particles enter the cyclone and then return to the inlet duct or even escape by the inlet.