入口弯管对矿用轴流通风机气动性能影响的数值研究

以某大型矿用低压轴流式通风机为研究对象, 采用气体动力学性能试验和数值模拟的方法研究了不同入口弯管对风机性能的影响, 重点分析了入口弯管引起的叶轮内部流动特征和损失分布的变化规律。研究结果表明, 风机入口采用弯管连接缩短了进口管道的轴向长度, 节省了地下空间, 但同时来流的均匀性受到影响。弯管内气流速度梯度较大, 管道内侧易发生流动分离, 产生回流区, 增大了流体流动时的能量损失, 风机的整体性能下降。弯管与叶轮入口之间的连接长度会影响内部流场, 当附加直管段较长时, 来流均匀性得到提高, 风机性能有所改善。

Numerical Study for the Influence of Inlet Elbow on the Aerodynamic Performance of Axial Fan Used for Mine Ventilation

A large-scale low-pressure axial fan used in mine was taken in an aerodynamic performance test for investigating the influence of different inlet elbows on the performance of the fan by using numerical simulation method. The internal flow characteristics and the variation in the loss distribution of the impeller caused by inlet elbows were specially analyzed. Results show that the use of elbow for connection at the fan inlet shortens the axial length of the inlet pipe and saves underground space, but meanwhile brings some influence to the uniform distribution of the inlet flow. It is found that due to the higher velocity gradient of the airflow in the elbow, the flow separation is prone to occur inside the pipe, leading to a backflow zone, which increases the energy loss during fluid flows, leading to the deterioration of the overall performance of the fan. The length of the connection between the elbow and the inlet impeller will affect the internal flow field. With a longer section of additional straight pipe, the inlet flow becomes more stable and uniform, indicating the performance of the fan is improved.