Analysis and simulation of erosion of sand control screens in deep water gas well and its practical application

The occurrence of sand production in deep water gas well leads to faster airflow carrying sands and more serious erosion of the sand control screen. Screen erosion is easy to cause sand control failure, reduce production and increase the cost of later workover. In present study, the erosion of screens in deep water gas well is simulated by computational fluid dynamics (CFD). Based on the structure and performance of premium quality screens, star-shaped screens and wire wrapped screens, the screen geometric models and the pore geometric models which can be modified in stages to match the pore size change during the erosion process is established. The multi-angle screen erosion model of discrete particles is established based on the empirical screen erosion model and the impact angle function. After that, combined with the gas-solid phase coupling flow model, considering the inlet, outlet and wall boundary conditions of the screen and the pore, introducing the spatial discretization scheme and the pressure velocity coupling method, the gas-solid two-phase flow field and the erosion rate of the screen are iteratively calculated by under-relaxation method. Therefore, the numerical simulation of screen erosion in deep-water gas well is formed and it is applied to the wear analysis and the sand control screen optimization for the XX deep water gas well in the South China Sea. The results show that the multi-angle erosion model of discrete particles and the numerical simulation of screen erosion can accurately describe the process of high-speed airflow carrying sand to erode the screen in deep water gas well, and the sand control screen can be optimized according to the simulation results to prolong service life.