环流式旋风除尘器内流场的数值模拟

Numerical Simulation of Flow Field in Circumfluent Cyclone Separator

采用CFD模拟软件Fluent 6.2提供的雷诺应力模型(RSM)对环流式旋风除尘器内的流场进行了数值模拟研究。并与热线热膜风速仪实验测试结果进行了比较。模拟结果与实验结果基本吻合。结果表明:环流式旋风除尘器特殊的流路设计,避免了内外旋涡的相互干扰,增强了旋转速度,规整了流形,减小了强湍流对性能的影响,消除了旋风除尘器易产生的短路流和二次返混,提高了除尘效率,降低了设备的压降。通过对影响除尘器性能的局部涡进行分析,为进一步优化结构提供了参考依据。

The three-dimension flow field in circumfluent cyclone separator was simulated by using Reynolds stress model （RSM） with Fluent 6.2. The distributions of tangential and axial velocity at different section of the cyclone were measured by IFA-300 anemometer, and the experimental results consist well with the corresponding simulation results. Both the results show that the circumfluent cyclone separator is more available for particle separation than conventional cyclone separators since the peculiar inner chamber structure reduces the gas flux from the cone and lessens the dust entrained by it. Furthermore, the special fluid path design of the circumfluent cyclone separator shortens the moving distance of the fluid, avoids the disturbance between the inner and outer flow, and eliminates the secondary vortex and short circuit flow existing in conventional cyclones. All these improve the collection efficiency of the circumfluent cyclone and lower its pressure drop, Moreover, the local vortex in the cyclone was also analyzed, and the study is helpful both for understanding the flow mechanism in the circumfluent cyclone separator and for its further improvement.