陶瓷过滤器脉冲反吹系统内流场的数值模拟

将陶瓷过滤器滤管内流场简化为二维轴对称、可压缩、非稳态湍流流场 ,采用贴体网格和计算流体力学方法对脉冲反吹系统内流场进行了数值模拟。模拟结果表明 ,在脉冲反吹过程中 ,引射空间和滤管内、外流场均为非稳态流场。在气体引射过程中 ,喷吹气流与被引射气流的相互作用不断变化。在初始阶段 ,由于喷吹气体速度较小 ,引射器入口区域存在二次引射现象。随着喷吹气体速度的增大 ,引射气量也逐渐增加 ;当脉冲反吹过程临近结束时 ,管内气体首先在引射器入口外侧的集气室内流动 ,随后逐渐扩展到引射器内部区域。

Numerical simulation of unsteady flow field in pulse cleaning system of ceramic filter

On the basis of experimental results of instantaneous velocity, the flow in the entraining region of unsteady flow field in the pulse cleaning system of a ceramic filter is regarded as two dimensional, unsteady, compressible and axisymmetrical flow. The computation analysis shows that the interaction process between the pulsed jet and entrained gas can be observed. In the initial stage, there exist the secondary entrained phenomena because of lower jet pulsing velocity. The mass flowrate of entrained gas increased gradually, while increasing the jet pulsing velocity. The computed and measured transient velocities are in good agreement. The simulation result is useful to performance analysis and optimum design of pulse backing cleaning system.