不同入口偏心距旋风筒内流场的数值模拟

Numerical simulation on flow field inside cyclone with various entrance eccentricity

采用数值模拟方法对不同入口偏心距的旋风筒内气相流场进行了分析,重点考察了入口偏心距对流场非轴对称特性的影响。通过分析速度场、顶板下二次流和环形空间内的短路流,以及筒体内涡核的分布特征,发现随着入口偏心距由零逐渐增大,在偏心距e=16 mm之前流场分布的非轴对称性得到改善,同时削弱了顶板下方上灰环的存在以及短路流造成的尘粒逸出现象,涡核偏离几何中心的平均距离也逐渐减小;随着偏心距继续增大,以上参量的分布特性又复变差。

The numerical simulation method was applied to analyze the gas-phase flow field in the vortex cyclone at various entrance eccentricity, and the influence of the entrance eccentricity on asymmetric characteristics of the flow field was observed. After analysis on the velocity field, the secondary flow below the upper board, the short-circuit flow in the annular space and the distribution of the vortex core in the cyclone, it was concluded: with the entrance eccentricity increased from 0 to 16 mm, the asymmetric distribution of the flow field was relieved, the role of the upper dust loop weakened, and dust escape due to short-circuit flow reduced, and mean distance of the vortex core from the geometric axis gradually decreased; with the entrance eccentricity went on increasing, the distribution characteristics of the above parameters worsened again.