Multilayer shallow water models with locally variable number of layers and semi-implicit time discretization

JOURNAL OF COMPUTATIONAL PHYSICS

卷:364

Article

Bonaventura, Luca¹  Fernandez-Nieto, Enrique D.^2,3  Garres-Diaz, Jose^2,3  Narbona-Reina, Gladys^2,3 

[1] Politecn Milan, Dipartimento Matemat, MOX Modelling & Sci Comp, Via Bonardi 9, I-20133 Milan, Italy

[2] Univ Seville, Dept Matemat Aplicada 1, Avda Reina Mercedes 2, E-41012 Seville, Spain

[3] Univ Seville, IMUS, ETS Arquitectura, Avda Reina Mercedes 2, E-41012 Seville, Spain

关键词: Semi-implicit method;    Multilayer approach;    Depth-averaged model;    Mass exchange;    Sediment transport;   

DOI  :  10.1016/j.jcp.2018.03.017

来源: Elsevier

【 摘 要 】

We propose an extension of the discretization approaches for multilayer shallow water models, aimed at making them more flexible and efficient for realistic applications to coastal flows. A novel discretization approach is proposed, in which the number of vertical layers and their distribution are allowed to change in different regions of the computational domain. Furthermore, semi-implicit schemes are employed for the time discretization, leading to a significant efficiency improvement for subcritical regimes. We show that, in the typical regimes in which the application of multilayer shallow water models is justified, the resulting discretization does not introduce any major spurious feature and allows again to reduce substantially the computational cost in areas with complex bathymetry. As an example of the potential of the proposed technique, an application to a sediment transport problem is presented, showing a remarkable improvement with respect to standard discretization approaches. (C) 2018 Elsevier Inc. All rights reserved.

【 授权许可】

Free