Influence Of Double Bottom Height Of Suez Tanker On Hull Structural Strength And Optimization Design Of Amidships Profile

Suezmax tanker is one of the five main types of tankers in the world oil transportation umarket,and it is the largest tanker with full load that can pass through the Suez Canal.Based on the special geographical location of Suez Canal,the demand for this type of tanker will keep increasing for quite some time in the future.In order to improve the safety of tanker navigation,at the same time reduce the production cost and enhance the ship performance,and improve the economy of tanker structure,this thesis takes the double bottom height factor into consideration,takes the 158,000 tons Suez tanker as the research object,carries out the mid-section structure specification design of this tanker based on different double bottom heights,on the basis of which the cabin segment calculation model is established,the strength evaluation and weight statistics of the hull under different double bottom heights are carried out.On the basis of this model,the strength assessment and weight statistics of the hull at different double bottom heights were carried out,and the effects of stress distribution of the hull components under various sailing conditions were systematically discussed.The main contents are as follows:(1)The Direct Strength Analysis(DSA)method and its key technologies based on the HCSR code for large tanker structures are studied.A Suez tanker with a double-deck bottom height of 2650 mm is used as the research object,and a cabin section finite element model is established and DSA of the cabin section structure is carried out to evaluate the strength of the cabin section structure of the target vessel,and the feasibility of the yield strength of the tanker under the code is verified.(2)Analyze the influence of double bottom height variation on hull structure,based on the double bottom height calculation formula and hull structure size specification,take double bottom height 2350 mm,2500mm and 2800 mm as the research variables respectively,and carry out direct specification design for the mid-section of this tanker with different double bottom heights,and carry out mid-section specification check to verify the reliability of the design scheme.(3)Based on the mid-profile structural scheme designed by the aforementioned specifications,the geometric characteristics of ships with different double bottom heights are determined,and based on this,finite element models of compartments with different double bottom heights are established,DSA of compartment structures are carried out,the stresses of different members of each compartment model are analyzed,the weights of each compartment model are counted,and the influence of double bottom height factors on the strength and weight of the hull is studied to obtain a mid-profile design scheme more suitable for this tanker,which provides reference for the actual design of the ship structure.(4)On the premise of satisfying the strength equilibrium and in order to reduce the ship construction cost,the optimized design of the mid-profile of the tanker is carried out based on the specification calculation.The optimization algorithm combined with the specification calibration software is used to build the optimization simulation system by using the general optimization platform ISIGHT integration and calling Mars2000 software,to establish the parameter data flow containing the objective function,design variables and constraints and the optimization integration system,to select the simulated annealing algorithm,evolutionary algorithm and particle swarm algorithm as the optimization algorithm,and to complete the optimization of the mid-profile structure of the tanker.The design of the mid-profile structure of the tanker was completed by using simulated annealing algorithm,evolutionary algorithm and particle swarm algorithm.The optimization results show that the optimization method described in this thesis has good application value in the design of the hull structure,on the basis of the common structural code,the research on the lightweight structure of oil tankers is of great significance.