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Improved phase-field models of melting and dissolution in multi-component flows.

ABSTRACT: We develop and analyse the first second-order phase-field model to combine melting and dissolution in multi-component flows. This provides a simple and accurate way to simulate challenging phase-change problems in existing codes. Phase-field models simplify computation by describing separate regions using a smoothed phase field. The phase field eliminates the need for complicated discretizations that track the moving phase boundary. However, standard phase-field models are only first-order accurate. They often incur an error proportional to the thickness of the diffuse interface. We eliminate this dominant error by developing a general framework for asymptotic analysis of diffuse-interface methods in arbitrary geometries. With this framework, we can consistently unify previous second-order phase-field models of melting and dissolution and the volume-penalty method for fluid-solid interaction. We finally validate second-order convergence of our model in two comprehensive benchmark problems using the open-source spectral code Dedalus.

SUBMITTER: Hester EW

PROVIDER: S-EPMC7655769 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

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Improved phase-field models of melting and dissolution in multi-component flows.

Hester Eric W EW Couston Louis-Alexandre LA Favier Benjamin B Burns Keaton J KJ Vasil Geoffrey M GM

Proceedings. Mathematical, physical, and engineering sciences 20201021 2242

We develop and analyse the first second-order phase-field model to combine melting and dissolution in multi-component flows. This provides a simple and accurate way to simulate challenging phase-change problems in existing codes. Phase-field models simplify computation by describing separate regions using a smoothed phase field. The phase field eliminates the need for complicated discretizations that track the moving phase boundary. However, standard phase-field models are only first-order accur ...[more]

PMID: 33223948

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Dataset Information

Improved phase-field models of melting and dissolution in multi-component flows.

Publications

Improved phase-field models of melting and dissolution in multi-component flows.

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