Experimental and numerical investigation on the performance of a gas-solid cyclone with twisted baffles and roughened cone surface

Abstract

This paper presents a numerical and experimental study of a gas-solid cyclone to improve its performance by employing twisted baffles with a variable pitch length and roughened cone surface. Three-dimensional numerical simulations are performed utilizing ANSYS FLUENT software by employing the Reynolds Stress Model (RSM) and Eulerian-Lagrangian particle tracking scheme for the distribution of particle diameters from 0.1 to 14 μm. Numerical results demonstrate that the baffles have a major effect on the effective parameters of the cyclone such as tangential and axial velocities, turbulence intensity, pressure drop, the three-dimensional structure of eddies, and particle separation efficiency. It is found that the maximum amounts of tangential velocity, axial velocity, and separation efficiency correspond to 3-turn twisted baffles. With the installation of baffles, the generated vortices become stronger, enhancing the turbulence intensity and pressure drop compared to the case without baffles. The results reveal that the presence of baffles results in an enhancement in the separation efficiency of solid particles with a diameter of fewer than 2 μm. For the case of 3-turn twisted baffles and the inlet velocity of 30 m/s, the separation efficiency of particles with a diameter of 0.1 μm is >40%, indicating the proper performance of the device. In the present work, a cyclone with a 3-turn twisted baffle is fabricated and tested. The experimental results confirm the numerical results appropriately and demonstrate that the separation efficiency reaches 80% for the inlet velocity of 5.9 m/s.