Abstract
An algorithm for coupling SPH with an external
solution is presented. The external solution can be either another
SPH solution (possibly with different discretization) or a different
numerical solver or an analytical solution.
The interaction between the SPH solver and the external
solution is achieved through an interface region. The interface
region is defined as a fixed portion of the computational domain
that provides a boundary condition for the SPH solver. A ghost
fluid, composed by fully lagrangian particles (i.e. ghost particles)
covering the interface region, is used to impose the boundary
condition. The ghost particle evolution, including its position, is
integrated in time according to the field of the external solution.
The physical quantities of the ghost particles needed in the
integration scheme are obtained through an MLS interpolation
on the field of the external solution. When a ghost particle crosses
the boundary of the interface region, entering in the SPH domain, it evolves according to the SPH governing equation. The spatial distribution of the ghost particles can become largely non-uniform due to the forcing by the external solution. Thus, a packing algorithm is applied on the ghost particles in the interface region, to guarantee a particle distribution suitable for SPH operators. Since the ghost particles can exit from the interface region, a seeding algorithm is needed to introduce new ghost-particles. The algorithm is tested on several benchmarks and with the external solutions given by other SPH solvers with different discretizations and by analytical solutions. The technique is deeply investigated in terms of accuracy, efficiency and possible applications. Finally a coupled simulation involving a finite volume solver is presented.
Anno
2013
Tipo pubblicazione
Altri Autori
B.Bouscasse, S.Marrone, A. Colagrossi, A. Di Mascio
Titolo Volume
Proceeding of the 8th INTERNATIONAL SPHERIC WORKSHOP