全金属单螺杆泵工作性能的仿真与实验研究

基于计算流体力学(CFD),选用三维瞬态湍流动网格模型,对双头全金属单螺杆泵进行流体仿真分析,编写CG宏函数实现动网格中流域动边界的行星运动,仿真研究不同黏度和转速对泵工作效率的影响,同时对该型全金属螺杆泵在不同黏度和转速下进行实验研究。结果表明:在稠油热采环境中,油液黏度较低(50 m Pa·s),提高转速可以有效改善容积效率和泵效;在稠油冷采环境中,油液黏度较高(50 m Pa·s),提高转速泵效先增大后减小,转速过大会引起定转子接触碰撞频率、油液对转子的正压力以及油液对转子的摩擦阻力的增大,使得泵效降低,容积效率维持在较高水平;该泵更适合于黏度较高液体的输送。

Research on operating characteristic of metal progressive cavity pump using simulation and experimental method

Using FLUENT software, the double lobes metal progressive cavity pump was analyzed with the 3D dynamic mesh method, and the eccentric rotation of the rotor in the stator was studied. The CG macro function which could make the rotor rotate was proposed. The influence of different conditions on the pump performance was studied using simulation and experimental methods. The results show that in the environment of thermal recovery of heavy oil, the increase of the rotating speed can effectively improve the volumetric efficiency and pump efficiency for the oil of lower viscosity (<50 mPa·s); in the environment of cold production of heavy oil, when the rotating speed increases, the pump efficiency increases in the beginning and then decreases for the oil of higher oil viscosity (> 50 mPa·s). Because of the frequency of the contact between stator and rotor, the positive pressure and frictional resistance of the rotor increased with the increase of rotating speed, which makes the pump efficiency decrease. The increase of the speed can significantly improve the volumetric efficiency and overall efficiency of the metal progressive cavity pump for the conveying of a low viscosity liquid, but much higher speed also can cause the reduction of overall efficiency; volumetric efficiency and overall efficiency basically remain unchanged with the change of the differential pressure and the speed for the conveying of a high viscosity liquid; which is more suitable for the transportation of higher viscosity liquid.