Comparing approaches for numerical modelling of tsunami generation by deformable submarine slides
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Accepted version
Published version
Author(s)
Type
Journal Article
Abstract
Tsunami generated by submarine slides are arguably an under-considered
risk in comparison to earthquake-generated tsunami. Numerical simulations
of submarine slide-generated waves can be used to identify the important factors
in determining wave characteristics. Here we use Fluidity, an open source
finite element code, to simulate waves generated by deformable submarine
slides. Fluidity uses flexible unstructured meshes combined with adaptivity
which alters the mesh topology and resolution based on the simulation
state, focussing or reducing resolution, when and where it is required. Fluidity
also allows a number of different numerical approaches to be taken to
simulate submarine slide deformation, free-surface representation, and wave
generation within the same numerical framework. In this work we use a
multi-material approach, considering either two materials (slide and water
with a free surface) or three materials (slide, water and air), as well as a
sediment model (sediment, water and free surface) approach. In all cases
the slide is treated as a viscous fluid. Our results are shown to be consistent
with laboratory experiments using a deformable submarine slide, and
demonstrate good agreement when compared with other numerical models.
The three different approaches for simulating submarine slide dynamics and
tsunami wave generation produce similar waveforms and slide deformation
geometries. However, each has its own merits depending on the application.
Mesh adaptivity is shown to be able to reduce the computational cost without
compromising the accuracy of results.
risk in comparison to earthquake-generated tsunami. Numerical simulations
of submarine slide-generated waves can be used to identify the important factors
in determining wave characteristics. Here we use Fluidity, an open source
finite element code, to simulate waves generated by deformable submarine
slides. Fluidity uses flexible unstructured meshes combined with adaptivity
which alters the mesh topology and resolution based on the simulation
state, focussing or reducing resolution, when and where it is required. Fluidity
also allows a number of different numerical approaches to be taken to
simulate submarine slide deformation, free-surface representation, and wave
generation within the same numerical framework. In this work we use a
multi-material approach, considering either two materials (slide and water
with a free surface) or three materials (slide, water and air), as well as a
sediment model (sediment, water and free surface) approach. In all cases
the slide is treated as a viscous fluid. Our results are shown to be consistent
with laboratory experiments using a deformable submarine slide, and
demonstrate good agreement when compared with other numerical models.
The three different approaches for simulating submarine slide dynamics and
tsunami wave generation produce similar waveforms and slide deformation
geometries. However, each has its own merits depending on the application.
Mesh adaptivity is shown to be able to reduce the computational cost without
compromising the accuracy of results.
Date Issued
2016-02-28
Date Acceptance
2016-02-17
Citation
Ocean Modelling, 2016, 100, pp.125-140
ISSN
1463-5003
Publisher
Elsevier
Start Page
125
End Page
140
Journal / Book Title
Ocean Modelling
Volume
100
Copyright Statement
© 2016 The Authors. Published by Elsevier Ltd.
This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
License URL
Sponsor
Natural Environment Research Council (NERC)
Natural Environment Research Council (NERC)
Grant Number
NE/E013589/1
NE/K000047/1
Subjects
Submarine Slide
Tsunami
Numerical Modelling
Validation
Adaptive Mesh
Publication Status
Published