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Abstract: This paper deals with a new solid–fluid coupling algorithm between a rigid body and an unsteady compressible fluid flow, using an Embedded Boundary method. The coupling with a rigid body is a first step towards the coupling with a Discrete Element method. The flow is computed using a finite volume approach on a Cartesian grid. The expression of numerical fluxes does not affect the general coupling algorithm and we use a one-step high-order scheme proposed by Daru and Tenaud [V. Daru, C. Tenaud, J. Comput. Phys. (2004)]. The Embedded Boundary method is used to integrate the presence of a solid boundary in the fluid. The coupling algorithm is totally explicit and ensures exact mass conservation and a balance of momentum and energy between the fluid and the solid. It is shown that the scheme preserves uniform movement of both fluid and solid and introduces no numerical boundary roughness. The efficiency of the method is demonstrated on challenging one- and two-dimensional benchmarks. [Copyright &y& Elsevier]

Abstract: In this paper, the authors present an efficient three-dimensional algorithm, based on the fully explicit matrix inversion free finite element version of the Characteristic Based Split (CBS) scheme, and apply it for the first time to the simulation of complex thermo-fluid-dynamic problems in domains containing simultaneously a fluid and a porous layer. The stability analysis recently developed for the two-dimensional version of the algorithm is here extended to the three-dimensional version. Unstructured grids have been successfully employed to solve complex interface problems. The present code produces an effective solution for complex 3D problems, and does not require large computing resources. The advantages deriving from the algorithm’s stability, the use of unstructured meshes and the low computing requirements make the present three-dimensional procedure a powerful and flexible tool for efficient modeling of real life problems. The present 3D code is used to solve both forced and natural convection in partially porous domains. [Copyright &y& Elsevier]

Abstract: This article describes a conservative synchronized remap algorithm applicable to arbitrary Lagrangian–Eulerian computations with nodal finite elements. In the proposed approach, ideas derived from flux-corrected transport (FCT) methods are extended to conservative remap. Unique to the proposed method is the direct incorporation of the geometric conservation law (GCL) in the resulting numerical scheme. It is shown here that the geometric conservation law allows the method to inherit the positivity preserving and local extrema diminishing (LED) properties typical of FCT schemes. The proposed framework is extended to the systems of equations that typically arise in meteorological and compressible flow computations. The proposed algorithm remaps the vector fields associated with these problems by means of a synchronized strategy. The present paper also complements and extends the work of the second author on nodal-based methods for shock hydrodynamics, delivering a fully integrated suite of Lagrangian/remap algorithms for computations of compressible materials under extreme load conditions. Extensive testing in one, two, and three dimensions shows that the method is robust and accurate under typical computational scenarios. [Copyright &y& Elsevier]