Research On The Calculation Method Of Ship Stability Based On 3D Modeling With CATIA

Stability of ship has been an important indicator of safety performance of the ship, which is related to personnel and property safety of the ship and marine environmental protection and other aspects, fast and much more precious ship stability calculation are indispensable during the design process. Traditional calculation method of stability in determining the geometric elements of ship in free-floating state, two-dimensional cross-sectional lines and waterline determine the location of the intersection and numerical integration methods is used. Main disadvantage of doing so is that two-dimensional method often depends on the accuracy of numerical integration and selected number of data, in which data input is time-consuming and precision of calculation is limited. If displacement volume of ship is carried out by a two-dimensional numerical method, the more the number of cross-section being chosen, the higher precision it is. In addition, intersection and integration calculation is needed during arbitrary floatation, which is also time-consuming. With the development of computer technology, capabilities of three-dimensional modeling is becoming better and calculations of ship stability gradually shift to it. By necessary secondary development, stability and other performance of ship come into effect. CATIA is a powerful three-dimensional design software and it provides a secondary development interface and make it possible being platform for stability calculations based on the three-dimensional model. The main researches are as follows:The method of solid model based on CTAIA is studied and secondary development in the CATIA platform through VB has been carried out, which reduce the repetitive operation. The method for simplify the modeling process provide the 3D data geometrical model for the stability calculation.The position of water plane is established in free floating state in the CATIA platform, which is both the three-dimensional problem. On the basis of the intersection of hull surface and water plane, the geometric elements needed in the stability calculation can be obtained, including the area of water plane, moment of inertia of water plane, displacement volume, the coordinates of center of buoyancy.Based on the method above, hydrostatic data and the intact stability of ship in free-floating condition has been calculated. The example results show that the method proposed in this paper can simplify the operation, ensure the accuracy, and can provide the basis for the calculation of probability damage stability.