蜗壳式旋风分离器全空间三维时均流场的结构

采用激光多普勒测速系统（LDV）对蜗壳式旋风分离器全空间内三维湍流的时均流场进行了实验测定与分析，重点讨论了灰斗、环形空间和排气管的流场特点.分离空间内时均流场是外侧准自由涡与内侧准强制涡的典型结构.环形空间的入口部位有多个纵向二次涡，其他大部分空间顶部出现纵向二次环流，切向速度和径向速度的分布呈现非轴对称性，入口气量沿高度分布不均匀.灰斗的顶部也存在纵向二次环流.排气管内轴向速度分布与分离空间内的分布形态迥异.

THREE-DIMENSIONAL TIME-AVERAGED FLOW STRUCTURE IN CYCLONE SEPARATOR WITH VOLUTE INLET

Time-averaged velocities of three-dimensional turbulent flow field in a cyclone separator were measured by Laser Doppler Velocimetry. The features in the flow field, especially in dust hopper,annular space and outlet tube, were discussed and analyzed. In the separation space, the outer vortex can be approximately regarded as quasi-free vortex and inner vortex as quasi-forced vortex. There were many secondary lognitudinal eddies in the entrance of the annular space, while a secondary lognitudinal flow existed near the roof of cyclone at a majority of azimuthes except the entrance. The distribution of time-averagel tangential and radial velocity was asymmetric in the annular space. The gas flux in the entrance was uneven along the axial direction. A secondary lognitudinal flow still existed near the roof of dust hopper. The distribution of time-averaged axial velocity in the outlet tube was very different from that in the separation space.