Finite Element Analysis And Optimization Of Bulk Carrier Based On Parametric Modeling

Common Structural Rules for bulk carriers is the first time for a type of ship to unify the ship construction rule since IACS found. New rules aim at satisfying with the requirement of stronger, more durable and suitable of a ship. Compared with old rules, the concept of corruptive allowance is added, its safety increases obviously. But the ship is a complex surface buildings, most of the weight of ship is the weight of steel. Corruptive allowance that CSR requires will increase the use of steel and the weight of the ship structure, make the cost rising. Therefore, on the precondition of meeting the requirements, construction requirements and specification, the paper optimizes the hull structure to make the weight lighter, which improves material utilization, saves construction costs and increases the the ship's carrying capacity.This paper expounds the safety rules development of bulk carriers, explains the background and signification. Introduce the status and trends of ship structure optimization design. Discuss the basic process of CSR direct calculation. Take a 57000DWT bulk carrier as an example to analyze, the calculation will be accomplished by FEM software MSC.Patran& Nastran, the main procedure is creating the parametric finite element model. I use CSR-DSA which is latest developed by CCS to automatically load and assess, including yield strength calculation, the buckling strength calculation and the detailing stress assessment. Then I use multi-disciplinary design optimization software-iSIGHT to integrate MSC.Patran&Nastran, write simulative code. Selecting the thickness of plate, flat bar, T section and panel as the optimized variables, various loading conditions should smaller than the maximum allowable stress as constraint according to the yield strength calculation of CSR direct calculation, hull structural weight as objective function. I select the Multi-Island Genetic Algorithm to optimize the structural dimensions of hull structure, so that I get the lightest weight of the hull structure.The sizes of hull structure are optimized from angle of numerical calculation, satisfying result is obtained. This paper provides a new method and idea that research, develop and design a ship.