离心叶轮背叶片的直径计算

Calculation of diameter of backvane on centrifugal impeller

在化工泵、渣浆泵的离心式叶轮盖板外侧设置的背叶片,由于缺乏计算背叶片直径的规范及方法,造成确定这一参数的随意性,降低了背叶片应有的水力功能.以旋转流体内流体压力分布规律为基础,通过数学分析与定量积分运算,获得在后盖板外侧设置背叶片和前、后盖板外侧均设置背叶片的2种叶轮结构中,为完全平衡叶轮轴向力,背叶片直径所应满足的代数求解方程,该方程可以准确确定背叶片几何尺寸,避免了背叶片结构设计中的随意性.

In design practice of backvane outside the shroud of centrifugal impeller in chemical and slag- pulp pumps, diameter of backvane is often determined randomly because of lack of its design standards and methods, so that the hydraulic function due to the backvane is decreased. Based on pressure distribution in a rotating fluid and by means of mathematic analysis and quantitative integral calculation, the algebraic equations were obtained to find out the backvane diameter which would balance entirely the-axial thrust on the impeller with backvane outside its back shroud or outside its both front and back shrouds. These equa- tion could be used to determine accurately the geometric dimension of the backvane and the randomness above mentioned would be avoided.