LS-DYNA의 유체-구조 연성 해석기법을 이용한 슬로싱 및 슬래밍 응답해석

Abstract

As the cargo tank size and configuration of LNG carrier grows in response to the global increase in demands for LNG and the necessities of its economical transportation, sloshing impact loadings may become one of the most important factors in the structural safety of LNG Cargo Containment Systems (CCS). As the size of bow flare and the width of flat stern shape also grow in the modern large containerships for the extension of deck area and the improvement of propulsive efficiency, slamming impact loadings may be important factor in their structural safety assessment.

With the advent and ongoing advances in computational capabilities and its sophisticated tools, such as highly accurate dynamic nonlinear simulation code LS-DYNA, etc., shock response analyses, such as sloshing and slamming, have been actively carried out for more exact prediction of impact loadings together with tests and/or experiments, using Fluid-Structure Interaction (FSI) analysis technique.

In this study, to understand the characteristics of shock response behaviors of tank sloshing and wedge water entry problems and to enhance the shock response analysis technique, numerical simulations of 2D tank sloshing and 2D wedge slamming were performed using FSI analysis technique and ALE2D option of LS-DYNA code. Verifications were also carried out for the enhancement of simulation capability through the comparison of simulation results to experimental ones. Diverse parameters could be examined because of very efficient computational time using 2D simulation problems with recent R4.2.1 version of LS-DYNA ALE2D option. It could be confirmed that relatively good agreements of the analysis results were obtained compared to the experimental ones, and several parameters in the coupling algorithm and the mesh size in the shock area greatly affected the shock responses.