Modelling Strategies to Simulate the Fluid-Structure Interaction of Amphibious Aircraft Float Structure

Abstract

In this paper, the modelling strategies of Fluid-Structure Interaction impact simulation between amphibious aircraft float structure and water are investigated. Fluid-structure interaction in the form of constant velocity hydrodynamic impact was numerically modelled using finite element software by employing the coupled Eulerian-Lagrangian method. Four types of modelling strategies of the float, i.e., (1) full shell, (2) full solid, (3) multi-stage multi-scale, and (4) concurrent multi-scale modelling, are implemented and compared to obtain the most accurate model to obtain stress distribution on the float structure components. The modelling procedure and the advantages and disadvantages of each strategy are discussed comprehensively. The results show that the simulation using the structure modelled as shell elements is the most accurate strategy to obtain stress distribution on the float structure components while the solid elements model is the worst since the stresses predicted by using this model is lower than that of the shell elements model, especially when insufficient elements in the thickness direction is used. The multi-stage multi-scale in terms of shell-to-solid sub-modelling can be an alternative strategy since the results are similar to that using the shell geometry model. The concurrent multi-scale modelling, on the other hand, predicts acceptable stress values with a reasonable computational resource while maintaining computational accuracy and efficiency.