The present study addresses the development and validation of a smoothed particle hydrodynamics (SPH) method, particularly to examine its feasibility and capability in hydrodynamics and dynamics of aircraft during ditching. The developed method solves the weakly compressible Navier-Stokes equations coupled with six-degree of freedom dynamics to achieve an accurate prediction of the interaction between the aircraft and the fluid. In this SPH method, a dummy particle wall-boundary condition is automatically implemented to meet the requirement of application on geometrically complex engineering problems. An efficient particle search strategy merging the ideal of Cell-linked list with Vertlet list is proposed to speed up the neighbor particles search process. The present SPH method uses an OpenMP memory-shared parallelization in conjunction with Z-curve reordering to accelerate the computation. Validations have been performed on several classic hydrodynamic problems, where good agreements were achieved via comparing with documented experimental results. The developed SPH method is applied to predict the ditching event of a complex helicopter model. Results demonstrate the ditching process, indicating that the method can be potentially used in aircraft ditching applications.
The water ditching characteristics of a three-dimensional helicopter model with various ditching angles are numerically investigated by using an in-house smoothed particle hydrodynamics (SPH) solver which solves the Navier-Stokes equations and six degree-of-freedom in a coupled way. Validation is performed on two-dimensional wedge water entry problem, where good agreement is achieved via comparing with documented experimental results. The ditching events of a complex helicopter model with both vertical and forward speed are simulated by the SPH method. The results indicate helicopter would suffer a more violent impact with a lower initial incident angle and a low pressure region creates rear suctions which will pitch up the helicopter when the suctions are strong enough.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.