Acoustic Fluid Structure Interaction with Smoothed Particle Hydrodynamics Leveraging Parallel Computing on GPUs

摘要

The numerical simulation of physical phenomena is gaining popularity in all fields of engineering as computing capabilities grow rapidly. Replacing costly experiments, cheap and fast numerical simulations can be used to augment multibody dynamic models with flexible bodies as well as fluid structure interaction. Despite tremendous improvements on existing acoustic simulation methods, fluid structure interaction between multibody systems and surrounding gases or liquids is still particularly challenging to model. In this paper, the potential and limits of a meshless Lagrangian technique, called Smoothed Particle Hydrodynamics (SPH) are investigated with focus on acoustic fluid structure interaction. Similar to formulations for free surface flow, the SPH approximation is applied on the compressible Navier-Stokes equations. Combined with constitutive equations, the SPH approach is used to model both bulk flow and pressure wave propagation at the same time. The problem is resolved in its full nonlinear complexity since linearizations are avoided. Computational experiments, carried out for the verification of the new approach indicate that SPH models sound propagation accurately. Furthermore, sound excitation due moving boundaries shows good agreement with analytic solutions. However, this study also indicates that current approaches for the modeling of boundaries, such as rigid walls, are deficient and need to be improved in order make SPH applicable for the simulation of acoustic fluid structure interaction. Nonetheless, SPH is well suited to model liquid fluid structure interaction. Demonstrating potential applications, the motion of rigid bodies is simulated under forces resulting from liquid flow. The numerical experiments presented, draw on a fast, massively parallel GPU implementation of the SPH algorithm which is also discussed briefly.