TY - JOUR
T1 - Multi-Mesh-Scale Approximation of Thin Geophysical Mass Flows on Complex Topographies
AU - Tai , Yih-Chin
AU - Vides , Jeaniffer
AU - Nkonga , Boniface
AU - Kuo , Chih-Yu
JO - Communications in Computational Physics
VL - 1
SP - 148
EP - 185
PY - 2020
DA - 2020/11
SN - 29
DO - http://doi.org/10.4208/cicp.OA-2019-0184
UR - https://global-sci.org/intro/article_detail/cicp/18426.html
KW - Multi-mesh-scale approach, complex topography, shallow flows, unstructured mesh,
vertex-centered formulation.
AB - <p style="text-align: justify;">This paper is devoted to a multi-mesh-scale approach for describing the dynamic behaviors of thin geophysical mass flows on complex topographies. Because the
topographic surfaces are generally non-trivially curved, we introduce an appropriate
local coordinate system for describing the flow behaviors in an efficient way. The complex surfaces are supposed to be composed of a finite number of triangle elements. Due
to the unequal orientation of the triangular elements, the distinct flux directions add
to the complexity of solving the Riemann problems at the boundaries of the triangular
elements. Hence, a vertex-centered cell system is introduced for computing the evolution of the physical quantities, where the cell boundaries lie within the triangles and
the conventional Riemann solvers can be applied. Consequently, there are two mesh
scales: the element scale for the local topographic mapping and the vertex-centered
cell scale for the evolution of the physical quantities. The final scheme is completed by
employing the HLL-approach for computing the numerical flux at the interfaces. Three
numerical examples and one application to a large-scale landslide are conducted to examine the performance of the proposed approach as well as to illustrate its capability
in describing the shallow flows on complex topographies.</p>