Numerical Simulation on the Erosive Wear inside the Subsea Capping Stack

Subsea capping stack is a kind of emergency rescue device and it is used for emergency rescue after the failure of underwater well control. In order to understand the wear situations of subsea capping stack under different working conditions, its internal flow under different working conditions was numerically simulated using CFD. The severely worn positions were determined by analyzing the distribution of the wear rate inside the pipeline under five working conditions. In addition, its structure was optimized. The analysis results show that when the main vertical pipe is opened (working condition 1 and 2), the maximum wear rate is lower and the wear is mainly distributed near the diversion hole of the main vertical pipe; when the main vertical pipe is closed, the maximum wear rate is increased obviously and the severely worn positions are located on the outer side wall surface of the downstream of the right angle pipe and the inner corner of the right angle pipe; and replacing the right angle pipe structure with the blind tee can significantly reduce the wear rate there. The research results can provide a reference for the structural design and optimization of the subsea capping stack and are conducive to speed up the research progress of subsea emergency devices in China.