DDZ 型墙装式轴流风机具有两面角几何扭曲叶片,可以明显改善风机的进口流动条件,使风机具有流量大、压力低、效率高、噪声小和气流分布均匀等特点。计算分析了这种风机进口附近的流动情况,建立了风机进口处的空气动力学模型。根据此模型计算了附着涡切向环量在子午面内的诱导速度。结果表明,诱导速度使叶轮进口处,尤其是叶轮外缘处的流动条件明显改善。这从理论上阐明了这种风机性能优良的根本原因。 DDZ-type wall-mounted axial fan with double-sided geometric distortion of the blade, can significantly improve the fan inlet flow conditions, the fan has a large flow, low pressure, high efficiency, low noise and uniform air distribution and so on. The flow around the inlet of the fan is calculated and analyzed, and the aerodynamic model of the inlet of the fan is established. According to this model, the induced velocity of tangential loop of adherent vortex in meridional plane was calculated. The results show that the induction velocity significantly improves the flow conditions at the impeller inlet, especially at the outer edge of the impeller. This theoretically illustrates the root causes of this excellent fan performance.