The Effect On The Axial Oil And Gas Multiphase Pump Performance By The Axial Spacing Of The Rotor-stator

Mixing of oil and gas transmission has become a hotspot of modern in the exploitation of oil fields. The multiphase pump what gets people’s attention is the major equipment to transport oil and gas. As the complexity of object transported flow, the multiphase pump design theory has still not perfect at present. The second generation prototype of the YQH-100is put as a main research object in this thesis. When build a machine to slove three-dimensional model and calculate using mixture model, standard k-s turbulent model, velocity pressure coupling calculation using simple arithmetic to give numerical calculations of the whole flow field of the pump. Based on the analysis of the pressure distribution, velocity distribution and phase distribution, the whole machine internal flow characteristics are discussed.Axial force is one of the major issues affecting the safe and reliable operation of the pump. The helico-axial oil-gas multiphase pump will produce a large axial force during operation. This article analyzes the causes of the axial force generated and the fluid flow characteristics, that the theoretical calculation formula of axial force of the pump. Meanwhile, when the use of CFD numerical simulation techniques to analysis of the axial force of the pump, the results show that the axial force with the of increases gas rate and flow rate is reduced.In the third compression stage, considering together the change of the spacing of rotor-stator and between compression, it tskes rotor-stator-rotor-stator-rotor spacing are (1)25-10-15-20mm degressive change,(2)10-15-20-25mm incremental change,(3)all15mm to give numerical calculations of the whole flow field of the pump. This paper analyzes each corresponding coupling surface flows with different trends change and the impact of each change of head and efficiency. The results showed that has a certain impact on the spacing continuously changing internal and external flow characteristics. In a particular trend, increasing the spacing can reduce flow impact and improve the flow instabilities, but also increases the losses along the way. Under the change trend of spacing between the selected three groups, the velocity distribution on the coupling surfaces between the compression stage with incremental change are more uniform than the other two groups, and under this trend the head and efficiency are higher than the other two groups with the increase of the gas rate.