Parametric Analyses of the Dynamic Response and Fatigue Life of a Compliant Vertical Access Riser with Internal Flow

Authors

Fuheng Li, Department of Marine Engineering, College of Engineering, Ocean University of China, Qingdao, Shandong Province, ChinaFollow
Haiyan Guo, Department of Civil Engineering, College of Engineering, Ocean University of China, Qingdao, Shandong Province, China
Xiaomin Li, Department of Civil Engineering, College of Engineering, Ocean University of China, Qingdao, Shandong Province, China
Zhen Liu, Department of Marine Engineering, College of Engineering, Ocean University of China, Qingdao, Shandong Province, China
Honglu Gu, Department of Marine Engineering, College of Engineering, Ocean University of China, Qingdao, Shandong Province, China
Peng Cui, Department of Marine Engineering, College of Engineering, Ocean University of China, Qingdao, Shandong Province, China

Abstract

Subsea interventions on wellheads can be directly performed from a platform using a compliant vertical access riser (CVAR), thereby incurring tremendous economic benefits. The dynamic response and the fatigue damage of a CVAR subjected to regular waves are important for assessing its application feasibility. Therefore, a reasonable numerical model is presented for assessing the damage to a CVAR considering the internal flow using the slender rod theory. The finite element method combined with a Newmark-β scheme is employed to discretize the equations and update the time integration. The Palmgren-Miner rule is applied for fatigue life prediction, focusing on the wave-induced dynamic response and fatigue life of a CVAR with various parameters, including the wave height and period, internal flow, and external current. The results demonstrate that the dynamic response and the fatigue life of the CVAR are relatively sensitive to the wave height and the external current. The tension and the displacement decrease with the increasing excitation frequency, but the opposite is true for the fatigue life. In addition, the internal flow has a weak influence on the CVAR.

Recommended Citation

Li, Fuheng; Guo, Haiyan; Li, Xiaomin; Liu, Zhen; Gu, Honglu; and Cui, Peng (2021) "Parametric Analyses of the Dynamic Response and Fatigue Life of a Compliant Vertical Access Riser with Internal Flow," Journal of Marine Science and Technology: Vol. 29: Iss. 5, Article 5.
DOI: 10.51400/2709-6998.2466
Available at: https://jmstt.ntou.edu.tw/journal/vol29/iss5/5