气井井下节流器冲刷腐蚀数值计算

摘要

井下节流技术是一种新的采气技术，但是喷嘴会受到气流的冲刷腐蚀，影响节流嘴的使用寿命。根据流体流动的基本定律，建立了喷嘴冲刷腐蚀的数学模型，运用SIMPLE算法解方程。根据数值计算的结果发现喷嘴的入口处和后端剪切应力比较大，冲刷腐蚀比较严重。喷嘴壁受到的剪切应力随入口压力和流体粘度的变大而升高，研究的结果可以为节流器喷嘴的设计提供指导。%Downhole choking technique is a new gas production technology, but nozzles are eroded by erosion-corrosion, which will affect service life of the choke. In this paper, according to the basic law of fluid flow, a mathematical model of nozzle erosion-corrosion was established. And SIMPLE algorithm was used to solve equations. The numerical calculation results show that the shear stress of nozzle at the entrance and the back-end is larger;the erosion-corrosion is more serious. The shear stress of nozzle increases with increasing of inlet pressure and viscosity. The study can provide guidance for the design of choke nozzle.