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Simulation and analysis of inhomogeneous flow field in pulsed electrofloatation |
DENG Xiao-Gang, ZHOU Xiong |
(Department of Machinery Engineering, Chongqing University of Science and Technology, Chongqing 401331, China) |
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Abstract Due to the largescale violent circumfluence in the traditional electrofloatation (TEF), there is interference to grown and floatation of the mixture of microbubbles and floccules, causing lower energy utilization efficiency. In this paper, a pulsed electrofloatation (PEF) method was proposed by using a square wave impulse direct current. Since the circumfluence in the inhomogeneous field generated by PEF is weaker than that by TEF, the energy utilization efficiency will be improved. Then the liquidbubble flow field of PEF was simulated by using Fluent of Ansys 13.0. The results showed that the inhomogeneous flow field in PEF has a more reasonable turbulence energy distribution and less violent circumfluence induced by microbubbles floating. This suggests that PEF is helpful to the formation and floatation of the bubblefloccules mixture. With the same electric current density, the power consumption of PEF is as low as 1/4-1/3 that of TEF, but a similar floatation effect has been reached compared with TEF, so the power consumption efficiency is much better.
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Received: 04 June 2012
Published: 30 November 2012
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