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Title: A variable resolution SPH scheme based on independent domains coupling
Variable resolution in Smoothed Particle Hydrodynamics is essential for simulating several engineering problems characterized by different scales, to the point that this topic is listed as one of the open SPHERIC Grand Challenges. This work presents a new multi-resolution algorithm for weakly compressible Smoothed Particle Hydrodynamics (WCSPH), where an approach based on a domain-decomposition strategy is adopted. The domain is divided in an arbitrary number of different zones, which are connected only through additional Dirichlet boundary conditions enforced by buffer regions. The physical quantities of SPH particles in the buffers are computed by means of a corrected SPH interpolation over adjacent sub-domains. Specifically, a second-order kernel correction procedure is employed to ensure the proper consistency and accuracy of the interpolation. To model the mass transfer between the sub-domains, a procedure based on the evaluation of the Eulerian mass flux at the domain boundaries is applied. Particles that belong to a specific zone are created/destroyed in the buffer regions and do not interact with fluid particles that belong to a different resolution zone. One major strength of the presented multi-resolution strategy is that there is virtually no limit to the number of resolution levels that can be deployed, therefore this new model is ideal for simulating multi-scale applications. The algorithm has been implemented in the DualSPHysics opensource code [2] and optimized thanks to DualSPHysics’ parallel framework. The algorithm has been tested on a series of different cases, showing promising results for both internal and free-surface flows.  more » « less
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Author(s) / Creator(s):
; ;
Fourtakas, G.
Date Published:
Journal Name:
Proceedings of the 2023 International SPHERIC Workshop
Page Range / eLocation ID:
Medium: X
Sponsoring Org:
National Science Foundation
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