Passive Heave Compensator Design and Numerical Simulation for Strand Jack during Lift Operation in Deep Water

Abstract

In this paper, the passive heave compensator for the strand jack lifting system is studied. An analytical model is developed, which considers the nonlinear characteristic of the compensator stiffness thus as to predict its response under different parameters accurately. This analytical model helps to find the feasible gas volume of the compensator. The comparative analysis is carried out to analyze the influence of key design parameters on the dynamic response of the compensator. In order to evaluate the effectiveness of the compensator, a coupling model of the strand jack lifting system is derived. The compensator efficiency is evaluated in terms of the lifted structure displacement and the strand dynamic tension. The numerical simulations are performed to evaluate the effectiveness of the compensator. Numerical results show that the compensator is able to significantly decrease the tension variation in the strands and the motion of the lifted structure.