立体循环一体化氧化沟(IODVC)导流板结构优化研究

Structural optimization of guide-plates in an integrated oxidation ditch with vertical circle( IODVC)

针对立体循环一体化氧化沟(IODVC)弯道流场存在的问题,利用计算流体力学(CFD)和Fluent计算方法,对IODVC流场进行了二维单相流模拟,探究导流板结构形式对弯道流速分布的影响.研究结果表明,在同等边界条件下,导流板的结构形式对IODVC内混合液的流态分布影响较大.与单导流板相比,双导流板可将流速大于0.25 m·s-1的区域占比提高9.5%,并改善了弯道出口断面流速分布,有效地减小了下沟道靠近隔板处回流区域;此外,适当延长导流板末端长度,可以进一步强化对IODVC内混合液的导控作用,当延长长度等于导流板半径时,效果最佳,大于0.25 m·s-1的流速区域占比达到44.21%,使IODVC内部流场更加趋于均匀.研究结果对IODVC的进一步优化和工程设计有一定的指导意义.

According to the existing flow-field issues of bend channel in integrated oxidation ditch with vertical circle（ IODVC） systems,computational fluid dynamics（ CFD） technique along with a Fluent code were used to perform a two-dimensional simulation of single-phase flow in an IODVC;subsequently,the effect of guide-plate structure on the velocity distribution in the bend channel was explored. The results indicated that the flow pattern would varied substantially with different guide-plate structures even with the same boundary conditions. Compared with single guide-plate,implementation of double guide-plates could enhance the percentage of flow regime that the liquid velocity was higher than 0.25 m·s-1by approximately 9.5%,and also optimize the velocity distribution near the outlet section of the bend channel,which consequently reducing the reversed-flow region near the rear of the division plate. In addition,appropriately prolonging the length of the end of guide-plate could direct the liquid flow behavior in the IODVC. The findings also suggested that when the extended length equaled to the radius value of the guide-plate,the flow behavior in the reactor was relatively optimum and the percentage of the flow regime that the liquid velocity was greater than 0.25 m·s^-1could reached - 44.2%,delivering more uniformity of flow behavior to the IODVC. Overall,the outcomes derived from this work can provide guidance for both the design and optimization of full-scale IODVC systems.