Water impact investigations for aircraft ditching analysis

Passenger safety under dynamic crash loading is of key importance in modern aerospace vehicle design. In particular, crash-landings on water, commonly known as ‘ditching’, are a complex event to understand and account for in structural design for crashworthiness. Structural responses are complex and severe, given the highly dynamic nature of the fluid in the impact zone. Through numerical modelling, a better understanding of the dynamics of the event can be gained and thus lead to the development of efficient structural design tools. Of key importance for ditching investigations is the ability of numerical methods to capture the high deformations of the fluid domain in such events. From the various numerical techniques developed thus far, a particular meshfree numerical method has shown great potential to model water impact problems, namely the Smoothed Particle Hydrodynamics (SPH) method. This thesis investigates the SPH capability available in the commercial Finite Element (FE) code LS-DYNA®, for water impact problems. Experiments have been conducted on rigid wedges impacting water, which were then simulated with the SPH method. Although certain limitations were experienced with the experimental results, a positive correlation was observed with the numerical technique, thus establishing SPH as a promising method for crashworthiness design. The direction of further evaluation of the SPH technique has been identified, with the ultimate aim of developing a simulation methodology for the design and advancement of crashworthy concepts for aerospace vehicles.