:study On The Mechanism Of Sand-preventing Pump Based On Swirl Flow And Its Parameter Optimization

Because the most of oil fields in our country are in the middle late development stage, the sand production in oil well is becoming more and more serious, as a result of it, it will have bad influence on wellbore lifting equipment, and it will also cause sand stuck and aggravate production costs. In this paper, the oil and sand can realize the separation by using hydrocyclone separation technology, which improves the effect of sand stuck of the Sucker rod pump, and solves the problem of the sand stuck.First, three kinds of sand stuck schemes in the sucker rod pump are put forward to, one of these is optimally selected according to its characteristics, and the overall structure of the sucker rod is designed perfectly. Its characteristics are a swirl flow device which is added to the top of Seoul where the swimming component in the sucker rod pump, as a result of it the separation of sand and oil can be realized.Second, the solid-liquid two-phase flow in the hydrocyclone are analyzed theoretically. The simulation method of solid particles are described, the basic characteristic of the solid-liquid two-phase flow is analyzed, the constant resistance, acceleration force and the uneven force on which the sand force is acted by fluid in the sucker rod pump are researched deeply.Third, virtual model of the swirl flow device is established by using Gambit software, after that meshing is conducted, surface meshing which is used by Quad/Pave and body meshing which is used by Tet/Hbrid,Tgrid are conducted, meanwhile, on the basis of the Fluent software, numerical simulation of the solid-liquid two-phase flow is conducted by using the VOF model and the turbulence model RSM.Last but not least, according to the result of the numerical simulation, different parameters which are influenced by swirl effect is analyzed, a conclusion is drew by analyzing these results.The separation improves better when the annulus area increases; The separation improves better when the spiral groove depth and the pressure drop increases; The separation remains substantially unchanged when the pressure drop and the content of sand increases; The separation remains substantially unchanged when the entrance velocity, export tangential and the pressure drop velocity increases.According to the above results what have been discussed, the optimal working conditions about the effect of preventing the sand is that spiral groove top diameter reaches 22 mm, the height of spiral groove is 15 mm and the helix angle is selected at 60 degrees.