中文摘要：

在保证料流均匀的条件下，建立变径变螺距螺旋轴参数化设计的计算模型，给出螺旋轴参数化设计的工程应用实例。然后根据基于面积平均加权函数的混合理论，建立在所设计螺旋轴驱动下物料流动的三维分析模型，通过数值模拟与分析，研究螺旋轴工作转速、螺径／螺距比对物料三维流动和混合均化效果的影响，探讨螺旋轴工作转速与物料输送性能之间的关系，得到螺旋轴流场的面积平均加权函数的分布云图及相应的结论，为变径变螺距螺旋轴的结构设计提供了理论依据。另外利用本研究内容所生产的变径变螺距螺旋轴已在企业中得到应用。

英文摘要：

The parametric design model of the screw shaft with variable diameter and variable pitch is established under the condition of ensuring even flow rate of material, and an example of engineering application of parametric design of screw shaft is given. By utilizing the mixture theory based on mean weighting function of area, a 3D analysis model of material flow under the drive of the designed screw shaft is built. Through numerical simulation and analysis, the influence of the working speed and diameter-to-pitch ratio of the screw shaft upon the three-dimensional flow and mixing effect of the material is researched, the relation between the working speed of screw shaft and the material conveying performance is discussed, and the distribution cloud figure of the mean weighting function of the area of screw axial flow field, at the same time, the corresponding conclusion are obtained, and which provides a theoretical basis for the structure design of screw shaft with variable diameter and variable pitch. The screw shaft with variable diameter and variable pitch produced by utilizing the contents of this research has been applied in enterprises.