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DOE OSTI · 1324262

Second order upwind Lagrangian particle method for Euler equations

Samulyak, Roman·Chen, Hsin -Chiang·Yu, Kwangmin
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Abstract

A new second order upwind Lagrangian particle method for solving Euler equations for compressible inviscid fluid or gas flows is proposed. Similar to smoothed particle hydrodynamics (SPH), the method represents fluid cells with Lagrangian particles and is suitable for the simulation of complex free surface / multiphase flows. The main contributions of our method, which is different from SPH in all other aspects, are (a) significant improvement of approximation of differential operators based on a polynomial fit via weighted least squares approximation and the convergence of prescribed order, (b) an upwind second-order particle-based algorithm with limiter, providing accuracy and long term stability, and (c) accurate resolution of states at free interfaces. In conclusion, numerical verification tests demonstrating the convergence order for fixed domain and free surface problems are presented.

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97 MATHEMATICS AND COMPUTINGgeneralized finite differencesmeshless methodsparticle methodssmooth particle hydrodynamics

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Samulyak, Roman, Chen, Hsin -Chiang, Yu, Kwangmin. 2016-06-01. Second order upwind Lagrangian particle method for Euler equations. https://doi.org/10.1016/j.procs.2016.05.543

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