对一种新型圆柱形叶片型线方程的分析  

Analysis of a Polar Coordinate Equation Related to a Novel Cylindrical Blade Contour

作　　者：严敬 王桃 黄泽钊 赵尔策 YAN Jing;WANG Tao;HUANG Ze-zhao;ZHAO Er-ce(School of Energy and Power Engineering,Xihua University,Chengdu,China,610039)

机构地区：[1]西华大学能源与动力工程学院,四川成都610039

出　　处：《热能动力工程》2020年第11期122-126,共5页Journal of Engineering for Thermal Energy and Power

基　　金：四川省教育厅重大培育项目(18CZ0016);国家重点研发计划“智能电网技术与设备”专项(2018YF0905200)。

摘　　要：为帮助离心泵设计人员准确认识与理解非等变角螺旋线这一新形型线的几何特性,消除广泛存在的对这一型线的性能与设计要求的误解,以数学方法为依据导出了这一曲线的极坐标方程和包角的限制条件,由此形成了在叶片设计中应用这一优势曲线的完整可行方法。叶片包角是离心叶轮圆柱形叶片的重要几何参数,有一种模糊认识,认为在使用等变角螺旋线选择包角值时,包角由设计人员自行确定,其值不受任何限制。在分析这一曲线的极坐标方程后,这一类曲线包角的选择仍然必须受到限制,这种约束是由曲线在进出口处的几何特征决定的,不同的叶片包角可取范围的上下限有不同的计算值,导出了这一限制区间由曲线特性决定的两个边界值的数学表达式,并按一般统计规律选择的最佳叶片包角只有进入这一区间时方可得到预期的结果。本文以试验对比结果证实了叶片设计新方法对改善叶片水力性能有积极作用。In order to help centrifugal impeller designers understand the geometrical features of non-equal changeable helical curve accurately and eliminate a general misunderstanding related to the features and design requirements of the contour,authors of this paper obtained restrictive conditions of the wrap angle of the contour.Wrap angle of the blades is an important geometrical parameter of cylindrical blades used in centrifugal impellers.A wrong hypothesis exists,that is,when selecting the wrap angle magnitude of non-equal changeable helical curve,impeller designers are completely free to determine the angle value.After analyzing the polar equation of the curve,impeller desiynels are completely decided by them selves to determine the angle value.The restrictions were determined by the boundary conditions at inlet and outlet of the curve,and the upper and the lower limits of the angle range are different for different blades.Authors also formulated the mathematical expressions of restrictions at two ends of the curve and emphasized that only when the selected wrap angle fell into the range,the desired results can be obtained.Tests indicated that the blade wrap angle within the obtained range can improve the hydraulic performance of impellers.

关 键 词：离心泵 圆柱形叶片 几何参数 设计 数学分析 

分 类 号：TH311[机械工程—机械制造及自动化]