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arXiv · 2107.11859

Techniques for second order convergent weakly-compressible smoothed particle hydrodynamics schemes without boundaries

Pawan Negi·Prabhu Ramachandran
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Abstract

Despite the many advances in the use of weakly-compressible smoothed particle hydrodynamics (SPH) for the simulation of incompressible fluid flow, it is still challenging to obtain second-order convergence even for simple periodic domains. In this paper we perform a systematic numerical study of convergence and accuracy of kernel-based approximation, discretization operators, and weakly-compressible SPH (WCSPH) schemes. We explore the origins of the errors and issues preventing second-order convergence despite having a periodic domain. Based on the study, we propose several new variations of the basic WCSPH scheme that are all second-order accurate. Additionally, we investigate the linear and angular momentum conservation property of the WCSPH schemes. Our results show that one may construct accurate WCSPH schemes that demonstrate second-order convergence through a judicious choice of kernel, smoothing length, and discretization operators in the discretization of the governing equations.

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BibTeXRIS

Pawan Negi, Prabhu Ramachandran. 2021-07-25. Techniques for second order convergent weakly-compressible smoothed particle hydrodynamics schemes without boundaries. https://doi.org/10.1063/5.0098352

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