Dynamic analysis of launch & recovery system of seafloor drill under irregular waves

• Published in: Ocean engineering Vol. 117; pp. 321 - 331
• Main Authors: Jin, Yongping, Wan, Buyan, Liu, Deshun, Peng, Youduo, Guo, Yong
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.05.2016
• Subjects: Cables; Compensation; Dynamic; Dynamical systems; Launch & recovery system; Launches; Marine; Nonlinear dynamics; Recovery; Sea beds; Sea water; Seafloor drill; The tension of the umbilical cable; Dynamic; Seafloor drill; The tension of the umbilical cable; Launch & recovery system
• ISSN: 0029-8018; 1873-5258
• DOI: 10.1016/j.oceaneng.2016.03.056

Based on the launch & recovery system of a seafloor drill, the nonlinear coupling mechanism among the movement of the ship, the umbilical cable, and the seafloor drill caused by irregular waves is investigated, and the dynamic model that considers the influence of the seawater resistance for launch & recovery system of seafloor drill is established in this paper. Under different sea state conditions, the movement of the seafloor drill and the tension of the umbilical cable are calculated and analyzed for the seafloor drill before entering water and at different water depths. The research results showed that there are significant differences in the movement of the seafloor drill and the tension of the umbilical cable for different stages. The seawater resistance has obvious inhibition effect on reducing the erratic fluctuation of the movement of the seafloor drill and the tension of the umbilical cable. The analysis results can provide theoretical guidance for the studying of heave compensation and the constant tension automatic control of the umbilical cable. •A dynamic model for launch & recovery system of seafloor drill is established.•Seawater resistance has obvious inhibition effect on the movement of seafloor drill.•Increasing sea state will increase the tension of the umbilical cable.•Increasing water depth will increase the period of the γ angle and δ angle.•Increasing water depth will decrease the amplitude of the γ angle and δ angle.