Research Of Structure Design And Strength Analysis For High-speed Catamaran In Offshore Wind-farm Maintenance

Due to the pressure on energy supply and environmental problems, the development ofoffshore wind power industry has been incorporated in the relevant national planning.Themaintenance work is very inconvenient and operation risk is very big for offshore wind farm,especially to the deepwater area.Under the condition of high-speed development in offshorewind, the requirements of ship in offshore wind-farm maintenance will be more and morebig, designing and builting ships for offshore wing-farm maintenance has become seriousproblems to be solved urgentlyBecause of the high speed, good stability,wave resistance, the advantages of flexiblemaneuverability and mobility, Catamaran are suitable for wind power maintenancework.Catamaran’ molded breadth is larger and length-breadth ratio is smaller, so thelongitudinal strength is easy to guarantee. When the catamaran confront with transversewave or oblique wave, transverse bending or torsion will appear,and bridges withstandtremendous horizontal bending moment and torque.The transverse strength and torsionalstrength is the key technology of structure design.It is important for how to determine thelink bridge transverse bending moment and torque more accurately, and ensure the enoughstrength.We chose a catamaran in offshore wind-farm as the research object in this paper andprocess structure design according to the overall layout.According to reference informationand specification recommendations, the design scheme of two different structure are studied,namely mixed framing and full transverse framing scheme. And we draw the basic structureand typical cross section diagram for structural design, calculate the load of catamaran,andprocess theory calculation for the strength of the connection bridge.Using software MSC. Patran/Nastran to set up whole ship structure finite elementmodel of the catamaran, we calculate and analysis13kinds of working condition under thecombination of longitudinal bending moment, horizontal bending moment and torque load,and get the detailed distribution of stress and deformation of the whole ship at last.Calculation results show that two kinds of structure stress level is about the same, but thetransverse framing quality is light, the transverse frame type model should be choosen in thechoice of the skeleton type.For connection bridge area which do not meet the requirementsof strength, we adjust its structure,have a new finite element calculation, and the resultsshow that the adjustment scheme satisfies the requirement of the finite element strength.This article research results and some conclusions obtained has a certain referencevalue for the ship’s structure design and optimization of this kind of form,and it also canprovide a reference basis for structure strength analysis of small catamaran in the future.