Experimental and numerical study on the performance and mechanism of a vortex-broken electrocyclone

Abstract

As the synthesis unit of a gas cyclone and electrostatic precipitator, electrocyclone has advantages in particle collection efficiency, capital outlay, and space occupation. This paper proposes a better combination of the gas cyclone and electric field based on the self-designed vortex-broken wing. The performances of the vortex-broken electrocyclone with different inlet velocities and working voltages were investigated by both experiments and numerical simulations. The flow field and electric field in the electrocyclone were obtained by large eddy simulation and solving the potential equation, respectively. The particles were modeled by the Lagrangian particle tracking model and the dynamic behavior of a representative particle was analyzed. The experimental results show that the vortex-broken electrocyclone can reduce the pressure drop and improve the collection efficiency simultaneously. However, the reduction in pressure drop is obvious at high inlet velocity, while the increment in collection efficiency is just the opposite. On the one hand, the simulated flow field reveals that the mechanism for the reduction in pressure drop is that the vortex-broken wing breaks up the inner vortex core, thereby yielding a static pressure recovery. On the other hand, the electric intensity and velocity have opposite directions in the key flow regions, thus affecting the force balance and changing particle trajectories. Further analysis of particle dynamics demonstrates that although the electric field force is far less than the drag force, the particle trajectory can be significantly changed over time. These findings can provide guidance for optimizing the technologies that incorporate electric fields and gas cyclones.