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arXiv · 1906.04167

Accelerated Piston Problem and High Order Moving Boundary Tracking Method for Compressible Fluid Flows

Zhifang Du·Jiequan Li
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Abstract

Reliable tracking of moving boundaries is important for the simulation of compressible fluid flows and there are a lot of contributions in literature. We recognize from the classical piston problem, a typical moving boundary problem in gas dynamics, that the acceleration is a key element in the description of the motion and it should be incorporated into the design of a moving boundary tracking (MBT) method. Technically, the resolution of the accelerated piston problem boils down to a one-sided generalized Riemann problem (GRP) solver, which is taken as the building block to construct schemes with the high order accuracy both in space and time. In this paper we take this into account, together with the cell-merging approach, to propose a new family of high order accurate moving boundary tracking methods and verify its performance through one- and two-dimensional test problems, along with accuracy analysis.

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Zhifang Du, Jiequan Li. 2019-06-09. Accelerated Piston Problem and High Order Moving Boundary Tracking Method for Compressible Fluid Flows. https://arxiv.org/abs/1906.04167

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