Study Of Dynamic Response Of Spar Platform Under Ship Collision

As a new type of deep-sea oil and gas platform,Spar platform has attracted wide attention from large amounts of researchers since it was successfully developed.It boasts several advantages such as good sports performance,suitability for deep-water operation,good flexibility and low maintenance cost.Thus,it is of great significance for oil and gas exploration into the deep sea when confronted with the grim situation of depletion of these resources.Before carrying out relevant research on the Spar platform,it is necessary to fully understand its performance.In addition,the sea condition in deep sea environment is complex,the platform is likely to encounter the passing ship`s impact due to error or when docking platform under the influence of wind,wave and flow.Therefore,this paper first studies the dynamic response of Truss Spar platform under the collision of ships and then calculates the hydrodynamic performance of the target platform under given environmental conditions.Finally,the response of the platform under the joint action of collision and environmental load is discussed.The marine platform has obvious nonlinear dynamic characteristics in response to the motion during the collision of ships.In order to study the motion response of the platform in the event of a ship collision,a Truss Spar platform was chosen as the analysis object.The finite element method numerical simulation method is used to simulate the collision process between a 5000-tonne supply ship and the target platform using the nonlinear explicit finite element software ANSYS / LS-DYNA.The collision position is the water surface position of the platform buoy.After the simulation,impact results,energy conversion and structural stress timing results.For the hydrodynamic performance of the Truss Spar platform,a three-dimensional hydrodynamic model of the platform is established by using ANSYS software.Based on the three-dimensional potential flow theory,the model is imported into the AQWA hydrodynamic software.By using the AQWA-LINE module computing platform under different frequencies of additional mass,additional damping and motion response amplitude operator hydrodynamic parameters,and the correct results as the basis for time-domain analysis.In the time domain analysis,considering the platform and its mooring system as a coupled system,the dynamic response of the platform and the mooring force under the combination of wind,wave and flow are considered.In the time domain,the DRIF module in AQWA software is mainly used to calculate the motion response and mooring tension of the platform under given environmental conditions.In addition,this paper also uses the DRIF module in AQWA software to load the collision time series results obtained by ANSYS / LS-DYNA software onto the platform to get the motion response of the platform under the combined action of impact force and environmental load.And through the analysis of all the results,we can know that the Truss Spar platform has good hydrodynamic performance,both the lower dynamic response and the mooring tension under given environmental conditions meet the specifications,and the platform structure will suffer some damages in the event of a ship collision deformation,and the collision force has a direct impact on the motion response of the platform,which will affect the operation efficiency and safety of the platform.The obtained results can provide some reference for the research of the subsequent Spar platform,which is of practical significance.