TITAN2D is a geoflow simulation software application, intended for geological researchers. It is distributed as
free software
Free software or libre software is computer software distributed under terms that allow users to run the software for any purpose as well as to study, change, and distribute it and any adapted versions. Free software is a matter of liberty, no ...
.
Overview
TITAN2D is a free software application developed by the Geophysical Mass Flow Group at the State University of New York (SUNY) at Buffalo.
TITAN2D was developed for the purpose of simulating
granular flows (primarily geological mass
flows such as debris avalanches and landslides) over
digital elevation model
A digital elevation model (DEM) or digital surface model (DSM) is a 3D computer graphics representation of elevation data to represent terrain or overlaying objects, commonly of a planet, moon, or asteroid. A "global DEM" refers to a discrete g ...
s (DEM)s of natural terrain.
The code is designed to help scientists and civil protection authorities assess the
risk of, and mitigate, hazards due to dry debris flows and avalanches.
TITAN2D combines numerical simulations of a flow with digital elevation data of natural terrain
supported through a
Geographical Information System
A geographic information system (GIS) is a type of database containing geographic data (that is, descriptions of phenomena for which location is relevant), combined with software tools for managing, analyzing, and visualizing those data. In a ...
(GIS) interface such as
GRASS
Poaceae () or Gramineae () is a large and nearly ubiquitous family of monocotyledonous flowering plants commonly known as grasses. It includes the cereal grasses, bamboos and the grasses of natural grassland and species cultivated in lawns a ...
.
TITAN2D is capable of multiprocessor runs.
A Message Passing Interface
(MPI) Application
Programming Interface
(API) allows
for
parallel computing on multiple processors, which effectively increases computational power, decreases computing time,
and allows for the use of large data sets.
Adaptive gridding allows
for the concentration of computing power on regions of special
interest. Mesh refinement captures the complex flow features that occur at the leading edge
of a flow, as well as locations where rapid changes in topography induce large mass and momentum fluxes. Mesh
unrefinement is applied where solution values are relatively constant
or small to further improve computational efficiency.
TITAN2D requires an initial volume and shape estimate for the starting material, a basal friction angle, and an
internal friction angle for the simulated granular flow. The direct outputs of the program are
dynamic representations of a flow's depth and momentum. Secondary or derived outputs include flow velocity, and such field-observable quantities as run-up height, deposit thickness, and inundation area.
Mathematical Model
The TITAN2D program is based upon a depth-averaged model for an incompressible
Coulomb continuum, a “shallow-water” granular flow. The conservation equations
for mass and momentum are solved with a
Coulomb-type friction
term for the interactions between the grains of the media and between the granular material
and the basal surface. The resulting
hyperbolic system
In mathematics, a hyperbolic partial differential equation of order n is a partial differential equation (PDE) that, roughly speaking, has a well-posed initial value problem for the first n-1 derivatives. More precisely, the Cauchy problem can be ...
of equations is solved using a parallel, adaptive mesh,
Godunov scheme. The basic form of the depth-averaged governing equations appear as follows.
The depth-averaged conservation of mass is:
:
The depth-averaged x,y momentum balances are:
:
:
See also
*
Geologic hazards
*
Lahar
*
Pyroclastic flow
A pyroclastic flow (also known as a pyroclastic density current or a pyroclastic cloud) is a fast-moving current of hot gas and volcanic matter (collectively known as tephra) that flows along the ground away from a volcano at average speeds of b ...
*
Debris flow
Debris flows are geological phenomena in which water-laden masses of soil and fragmented rock rush down mountainsides, funnel into stream channels, entrain objects in their paths, and form thick, muddy deposits on valley floors. They generally ...
*
landslides
Landslides, also known as landslips, are several forms of mass wasting that may include a wide range of ground movements, such as rockfalls, deep-seated slope failures, mudflows, and debris flows. Landslides occur in a variety of environments, ...
References
* ''Titan2D User Guide'', Release 2.0.0, 2007.07.09; Geophysical Mass Flow Group, University at Buffalo (http://www.gmfg.buffalo.edu).
* A.K. Patra, A.C. Bauer, C.C. Nichita, E.B. Pitman, M.F. Sheridan, M. Bursik, B. Rupp, A. Webber, A. Stinton, L. Namikawa, and C. Renschler
Parallel Adaptive Numerical Simulation of Dry Avalanches Over Natural Terrain ''Journal of Volcanology and Geophysical Research'', 139 (2005) 1-21.
* E.B. Pitman, C.C. Nichita, A.K. Patra, A.C. Bauer, M.F. Sheridan, and M. Bursik
Computing Granular Avalanches and Landslides ''Physics of Fluids'', Vol. 15, Number 12 (December 2003).
* M.F. Sheridan, A.J. Stinton, A. Patra, E.B. Pitman, A. Bauer, C.C. Nichita
Evaluating Titan2D mass-flow model using the 1963 Little Tahoma Peak avalanches, Mount Rainier, Washington ''Journal of Volcanology and Geophysical Research'', 139 (2005) 89-102.
* E.B. Pitman, C. Nichita, A. Patra, A.C. Bauer, M. Bursik and A. Webber
A Numerical Study of Granular Flows on Erodible Surfaces March 24, 2003.
* B. Rupp, M. Bursik, A. Patra, B. Pitman, A. Bauer, C. Nichita, R. Saucedo, J. Macias, 200
Simulation of Pyroclastic Flows of Colima Volcano, Mexico, Using the TITAN2D Program AGU/EGS/EUG Spg Meet., ''Geophysical Research Abstracts'', 5, 12857.
* E. Munoz, D. Palacios, L. Namikawa, M. Sheridan, C. Renschler
Contrast Between Computer Simulations and Field Observation of Popocatepetl Lahars ''Geophysical Research Abstracts'', Vol. 6, 04599, 2004, European Geosciences Union.
External links
Geophysical Mass Flow Group(TITAN2D Distribution Site)
*
Titan2d-mod (released in 2016, a version modified from titan 3.0.0, 2011)
Processors
{{DEFAULTSORT:Titan2d
Scientific simulation software
Geology software