К оценке динамической прочности на волнении безопорных подробных моделей судового корпуса

Abstract

Cross-disciplinary CAE-based calculations of ship movement and strains in fluid, at launching device, during ice interaction or in case of a navigation accident require very performant computers, and their results can neither differentiate specific movement shapes nor be checked by means of a physical experiment, so their verification is a very important task. Automated algorithms based on common assessment procedures for movement components and external forces made it possible to not only verify numerical calculations of apparent dynamics, but also to obtain justified and rational layouts for arrangement of external load monitoring sensors, as well as to refine these common procedures as a separate field of studies and use more accurate estimates of external forces in design algorithms. The task is to correctly transfer the obtained information on movement and pressure fields to the analytical model under straining. The model is support-free, so kinematic conditions must be imposed on it so as not to distort realistic stressed state. In the unsteady formulation, it is necessary to correctly consider inertial and damping properties of fluid and structure itself, ensuring correct transition to the quasi-static formulation. Computer-based algebra of PTC MathCAD software made it possible for the authors to develop software modules for three-dimensional motion calculations of ships with arbitrary hull shape and loading, as well as APDL ANSYS applications for applying the data on external loads in stress-strain state calculations of support-free FE model of ship in frequency and time domain. The authors managed to develop a viable open-source solution for a cross-software system meant for dynamic strength analysis of ships in waves, which can be upgraded by non-programmers.