高含气率下双螺杆多相混输泵泄漏分析及其对容积效率的影响

Leakage Analysis and Effect on Volumetric Efficiency of Twin-screw Multiphase Pump with Higher Gas Volume Fractions

对双螺杆多相混输泵的泄漏通道进行了分析,建立了简化后的混输泵泄漏的数学计算模型,包括建立齿顶间隙泄漏模型、齿根间隙泄漏模型、齿侧间隙泄漏模型。并利用泄漏模型结合双螺杆内部泄漏通道的分布特点和容积效率的计算公式提出了双螺杆混输泵容积效率的数学计算模型。利用已有文献中的试验数据验证了理论计算模型的准确性,并且计算与试验值进行对比并分析了高含气率下含气率、转速、介质粘度对混输泵容积效率的影响。结果表明:当含气率在80%～95%之间增大时,齿顶和齿根间隙的泄漏量随之减小,而齿侧间隙的泄漏量先减小后增大,泵的容积效率会随介质含气率的增加而增大;但当含气率大于95%时,泵的容积效率会急剧下降,所以在混输泵工作时应当尽量将含气率控制在95%以下。同时双螺杆混输泵的容积效率会随着转子转速的增大而提高,随着所输送介质的粘度的增大而增加。

The leakage path of twin-screw multiphase pump has been analyzed by the mathematical model on the leakage of multiphase pump.The model include top clearance of tooth,root clearance of tooth and flank clearance of tooth.The volumetric efficiency model of is also established.Then the models are verified by the results of literature.The effect of gas volume fractions（GVF）,rotate speed,fluid viscosity on volumetric efficiency is also studied.The results indicated that the leakage rate of top and root decreased but the leakage rate of flank decreased first and then increased when the GVF increased from 80%-95%,the volumetric efficiency also increased with the increasing of GVF.The GVF should bellowed 95% since the volumetric efficiency decreased sharply when the GVF95%.The volumetric efficiency will increase with the increasing of rotor speed and viscosity of fluids.