Erosion prediction of sub-sea Xmas tree based on CFD

摘要

Sub-sea vertical Xmas tree is one of the key equipment in the oil industry. Erosion caused by particles in the flow of oil and gas may lead to equipment failure or even interruption of oil exploitation. Therefore, it is important to figure out the characteristics of erosion in vertical Xmas tree. In the present work, the AISI 8630 erosion model and the Forder wall rebound model has been applied to study the erosion of production channel and choke valve in the tree. The maximum and average surface erosion amount are introduced to evaluate the erosion degree. The results show that for the production channel, erosion mainly occurs in the interior of the turning point of the channel and the interior of the downstream wall near the joint, and the most serious eroded area is located at the bottom of the downstream wall of the channel. Comparing the effects of blind pipe length, particle concentration, particle size and flow velocity on the erosion wear of the production channel, it is found that the flow velocity is the main factor affecting erosion. As the velocity of fluid increases, the maximum and the average surface erosion on the inner wall of production channel increase in a steep manner. For the choke valve, as the relative opening increases, the maximum erosion amount decreases sharply. However, compared with the production channel, the wear of the valve channel is much more serious, and more attention should be paid in industrial operations.