低Reynolds数净化器除尘效率的计算流体动力学仿真与优化

Dust Collection's Efficiency of Low Reynolds Purifier via Computational Fluid Dynamic Simulation and Optimization

为研究低浓度下等离子体空气净化器内粒子流动特性以及粒子的捕获过程,建立了静电场、气体流场和粒子运动场耦合的气固两相流Eulerian-Lagrangian混合湍流模型。运用有限差分法计算了多场耦合作用下不同空气流速、施加电压和粒子粒径对粒子运动轨迹的影响。将数值预测与试验结果进行了对比验证,较符合:不同流速(0.5、1.0、2.0 m/s)下的最大偏差为8.9%;不同线电压(6.8、7.2、7.6 kV)下的最大偏差是3.8%;不同粒径(2、5、10μm)下的最大偏差是6.8%,研究论证了该模型能较好地模拟除尘过程,在指导小型家用净化设备的设计和优化过程中有一定的应用前景。

To investigate the flow characteristics and the trapping process for dust particles in the plasma air precipitators, we built a mathematic model of gas-solid two-phase flux based on the Eulerian-Lagrangian hybrid turbulence model. The model realizes the coupling of electrostatic field, gas flow field and particle dynamic field. With the multi-field-coupling model and using the finite difference method, we calculated the flow details of the system affected by various air flow rates, voltages, and particle sizes. The calculation results are in good accordance with experimental results： under the designed operating conditions, the max biases are 8.9% among three velocities （0.5, 1.0, 2.0 m/s）, 3.8% among three voltages （6.8, 7.2, 7.6 kV）, and 6.8% among three particle sizes （2, 5, 10 μm）. The proposed model can simulate the dust collecting process of the plasma air precipitators. It is useful for designing and optimizing small household purification equipment.