A Volume-conservative PLIC algorithm on three-dimensional fully unstructured meshes

3次元非構造格子系における体積保存型PLIC法

伊藤 啓; 功刀 資彰*; 大島 宏之; 河村 拓己*

Ito, Kei; Kunugi, Tomoaki*; Ohshima, Hiroyuki; Kawamura, Takumi*

PLIC法はVolume-of-fluid法の一種であり、高精度な界面計算に用いられるが、複雑な幾何計算を要するため非構造格子系における研究は十分ではない。本研究では、3次元非構造格子系におけるPLIC法の提案を行う。まず、界面勾配等の計算に用いる手法を構築し、加えて、流体率輸送時に気液両相の体積を完全に保存する手法を開発する。検証解析により、開発したPLIC法が大きく歪んだ非構造格子系においても高精度な解析結果を与えることを確認する。

The PLIC (Piecewise Linear Interface Calculation) algorithm is one of the volume-of-fluid algorithms. However, the PLIC algorithm needs complicated geometrical calculations for the reconstructions of the interfaces in interfacial cells, and therefore, the PLIC algorithm on unstructured meshes have not been studied enough. In this paper, the authors propose a new PLIC algorithm on unstructured meshes with arbitrary-shaped cells. In the proposed PLIC algorithm, several methods are developed or implemented. In addition, the volume fraction transport is improved by developing a volume-conservative algorithm in which gas and liquid volumes are conserved perfectly during the transport. As a result of the verification and validation tests, it is confirmed that the proposed PLIC algorithm enables the numerical simulations of interfacial dynamic behaviors with high accuracy even on unstructured meshes with highly-irregular cell arrangement.