The Remodel And The Flow-field Simulation Of The Semi-spiral Suction Chamber In The Multiphase Pump

The main function of suction chamber is to keep the flow in the impeller well-distributed and to enhance the efficiency of the whole pump. To the multiphase pump, the separation of different phases should also be avoided. It is important have a good suction chamber for better performance of the multiphase pump.In this thesis, the three dimensional model of the YQH—100 multiphase pump,which is the third sample, is established with the software ProE, and three suction chamber with different wrapping angles are obtained. Numerical simulation have been conducted on the flow-field of the three suction models on three different volume fractions, and the velocity field, the pressure field and the gas distribution is analyzed. The optimal fracture face and cut-water angle is obtained through the analysis;the vortex intensity is a little influenced by the angle of cut-water, and the semi-spiral suction chamber with the angle of 67.5°between the cut-water and the horizon plane is the most suitable model; the circular transition between the suction chamber and the compressor can keep the flow-field even more well-distributed.The analysis shows that the method of the suction chamber remodeling based on the simulation results of the multiphase pump is applicable and effective, and the theory basis and reference have been offered to the similar suction chamber design. The major content of this thesis is as following:1. The proper geometry model is constructed on the basis of the fundamental theory of fluid machinery and fluid dynamics. The numerical analysis has performed with relative two-phase flow model,and the sensitive of the model to the second phase (gas) is specially considered.2. The inner flow-field of the suction chamber is simulated with the gas volume fraction of 30%, 50%, 80%. The quality of the suction chamber structure and the trend of the inner flow-field under different gas fraction is researched on the analysis of velocity, static pressre and the gas distribution.3. After the analysis of the suction chamber, the compressor is brought in. The numerical simulation has performed on these three gas volume fraction. And the key point is the intersection of the suction chamber and the compressor and the destablization of the impeller on the flow-field of the suction chamber.4. After the coupling of the suction chamber and the compressing stage, there is mutual influence between the two departments.the above analysis is on the influence of the suction chamber to the compressing stage,and the influence of the compressing stage on the velocity and pressure distribution on the outlet of the suction chamber.5. After the simulation of the inner flow-field, the flow on the outlet of the impeller inducer is researched to see if the total pressure and the head is up to the design standard.6. After the selection of the wrapping angle of the suction chamber, a circular transition is added between the outlet of the chamber and the compressor based on the flow-field inside the chambers, and the flow field in the two models are compared. The result shows the circular transition between the suction chamber and the compressor is significant to keep the flow-field even more well-distributed.