双螺杆泵流场动力特性的数值模拟

Numerical Simulation of Flow Field Dynamics Characteristics for Twin-screw Pump

提出一种新型高效、密封性能更优越的渐开线修形双螺杆泵,并基于有限容积方法与摆线型双螺杆泵进行对比,建立两种泵的数值仿真模型,分析其压力场、速度场等的基本规律及特性曲线,得出了双螺杆泵流道的容积效率。研究表明:流道压力随密封腔逐级增大,且同级压力由于泄漏作用呈减小趋势;流道螺槽内存在涡流现象,啮合区混合强烈,在转子与泵套壁面接触区域及啮合区存在负轴向速度,为主要泄漏区域;渐开线修形双螺杆泵容积效率相对较高,密封性能更优越。研究结果为螺杆泵开发以及性能预估提供了理论指导和依据。

A new kind of highly effective,sealing superiorly and involute-modified twin-screw pump was proposed,compared with cycloid twin-screw pump and based on limited volume method,the numerical simulation models of two kinds of pumps were established.By analyzing their pressure fields,velocity fields and so on basic rules,the twin-screw pumps flow channels＇ volumetric efficiency were obtained.The research indicates that the flow channel pressure progressively increases along with the sealed chamber,the peer pressure is in the tendency of reduction as a result of leakage;the eddy flow phenomenon exists in the flow channel spiral flute,the meshing area is mixed intensely,the negative axial velocity exists in the contact area of rotor and pump cover＇s wall surface and the meshing area which are the main leakage areas.Involute-modified twin-screw pump volumetric efficiency is relatively high,with superior sealing performance.The research findings will provide the theory basis for the later screw pump＇s development design.