双头单螺杆泵衬套型线分析

FEA for a double-helix single screw pump bush profile

针对双头单螺杆泵衬套在实际使用中受到流体压力、衬套外壳以及螺杆的作用,容易发生磨损和变形,影响螺杆泵的寿命和效率的问题,采用ANSYS软件对双头单螺杆泵衬套进行有限元仿真模拟。将衬套的有限元模型简化为平面应变模型求解,分析了3种常用型线双头单螺杆泵衬套在受到均匀压力与非均匀压力下,衬套内各点的变形、应力与应变的分布情况。模拟分析结果表明,在均匀压力作用下,普通内摆等距型线衬套的法向位移曲线呈正弦规律变化,其余2种呈V形变化,在1个周期内刚好有3个波峰、波谷,与衬套形状特征相对应;短幅内摆等距型线应力变化相对均匀,沿自然路径变化曲线呈U形。

The double-helix single screw pump bush is easily worn and deformed by the fluid pressure,outer shell and pump rod in actual application,resulting in affecting the life and efficiency of screw pump.Therefore,the bush is simulated by means of ANSYS software.The finite element model of the bush is simplified as plane strain model for solution.The quadrangle element mapping gridding classification method is used and the ultra-elastic solid element with two-dimensional four-node and mixed u-P equation is selected.The simulation result shows that under the uniform pressure,the normal displacement curve of the common hypocycloid equal-distance bush changes at sine rule,and the rest two change at V shape.Therefore,there are three wave crests and wave hollows within one period which accord with the feature of bush shape.The stress change of short hypocycloid equal-distance profile is relatively uniform and changes at U shape along natural route.