Simulation of shockwave - Structure interaction with the brinkman penalization method

This paper describes a method for the prediction of shock-structure interactions. The technique used is a penalization method in which additional terms are added to the equations of motion in regions designated as solids that bring the flow to rest inside and on their boundaries. The specific method used is called the Brinkman penalization method. A force is added to the momentum equations and a related work term is added to the energy equation. The basic equations are the compressible nonlinear Euler equations. Numerical simulations are described for both low amplitude fluctuations, such as those that occur in acoustic scattering problems, and high amplitude disturbances, such as occur in shock-structure interactions. The numerical method is a high-order accurate explicit time-marching scheme. Both a blended artificial dissipation scheme and explicit filters are used to suppress Gibbs oscillations and unresolved high wavenumber disturbances. The calculations are performed on a uniform grid and a parallelization strategy based on domain decomposition is used. Validation cases for acoustic scattering are performed for a benchmark problem and comparisons are made with an exact solution. For shock-structure interaction validation, comparisons are made with shock tube experiments of the diffraction of a shock wave by a triangular body. A general example is given for a more complicated structure with both internal and external shock interactions.