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anuga_core/documentation/user_manual/anuga_user_manual.tex
r5555 r5566 94 94 95 95 \noindent \anuga\index{\anuga} is a hydrodynamic modelling tool that 96 allows users to model realistic flow problems in complex geometries.96 allows users to model realistic flow problems in complex 2D geometries. 97 97 Examples include dam breaks or the effects of natural hazards such 98 98 as riverine flooding, storm surges and tsunami. … … 101 101 cells, the topography and bathymetry, frictional resistance, initial 102 102 values for water level (called \emph{stage}\index{stage} within \anuga), 103 boundary 104 conditions and forces such as windstress or pressure gradients if 105 applicable. 103 boundary conditions and forces such as rainfall, stream flows, windstress or pressure gradients if applicable. 106 104 107 105 \anuga tracks the evolution of water depth and horizontal momentum … … 223 221 As such it cannot resolve vertical convection and consequently not breaking 224 222 waves or 3D turbulence (e.g.\ vorticity). 225 \item The surface is assumed to be open, e.g. \anuga cannot model226 flow under ceilings or in pipes223 %\item The surface is assumed to be open, e.g. \anuga cannot model 224 %flow under ceilings or in pipes 227 225 \item All spatial coordinates are assumed to be UTM (meters). As such, 228 226 ANUGA is unsuitable for modelling flows in areas larger than one UTM zone 229 227 (6 degrees wide). 230 \item Fluid is assumed to be inviscid 228 \item Fluid is assumed to be inviscid  i.e.\ no kinematic viscosity included. 231 229 \item The finite volume is a very robust and flexible numerical technique, 232 230 but it is not the fastest method around. If the geometry is sufficiently … … 236 234 \item Frictional resistance is implemented using Manning's formula, but 237 235 \anuga has not yet been fully validated in regard to bottom roughness 238 \item ANUGA contains no tsunamigenic functionality relating to239 earthquakes.236 %\item ANUGA contains no tsunamigenic functionality relating to 237 %earthquakes. 240 238 \end{itemize} 241 239 … … 247 245 This section is designed to assist the reader to get started with 248 246 \anuga by working through some examples. Two examples are discussed; 249 the first is a simple example to illustrate many of the ideas, and247 the first is a simple example to illustrate many of the concepts, and 250 248 the second is a more realistic example. 251 249 … … 2329 2327 \end{itemize} 2330 2328 Note specifying both center, radius and polygon will cause an exception to be thrown. 2329 Moreover, if the specified polygon or circle does not lie fully within the mesh boundary an Exception will be thrown. 2331 2330 2332 2331 \bigskip … … 2353 2352 Module: \module{shallow\_water.shallow\_water\_domain} 2354 2353 2355 This is a general class for inf iltrationand abstraction of water according to a given rate of change.2354 This is a general class for inflow and abstraction of water according to a given rate of change. 2356 2355 This class will always modify the \code{stage} quantity. 2357 2356 … … 2446 2445 \end{itemize} 2447 2446 2448 The user can specify different culvert routines. Hower ANUGA currently specifiesone, namely the \code{boyd\_generalised\_culvert\_model} as used in the example below.2447 The user can specify different culvert routines. Hower ANUGA currently provides only one, namely the \code{boyd\_generalised\_culvert\_model} as used in the example below. 2449 2448 2450 2449 \bigskip … … 2772 2771 Module: \module{shallow\_water.data\_manager} 2773 2772 2774 Obtain flow $[m^ 2]$ perpendicular to specified cross section.2773 Obtain flow $[m^3/s]$ perpendicular to specified cross section. 2775 2774 2776 2775 Inputs: … … 3065 3064 \subsection{DEM Format} 3066 3065 3067 A DEM file i s a NetCDF representation of regular DEM data.3066 A DEM file in \ANUGA is a NetCDF representation of regular DEM data. 3068 3067 3069 3068 … … 3179 3178 \] 3180 3179 in which $\eta$ is the Manning resistance coefficient. 3180 The model does not currently include consideration of kinematic viscosity. 3181 3181 3182 3182 As demonstrated in our papers, \cite{ZR1999,nielsen2005} these 3183 equations provide an excellent model of flows associated with 3184 inundation such as dam breaks and tsunamis. 3183 equations and their implementation in \ANUGA provide a reliable 3184 model of general flows associated with inundation such as dam breaks 3185 and tsunamis. 3185 3186 3186 3187 \section{Finite Volume Method} … … 3863 3864 If no value is specified, the default attribute is taken to be the 3864 3865 first one. 3866 3867 Note that the Geospatial\_data object currently reads entire datasets 3868 into memory i.e.\ no memomry blocking takes place. 3869 For this we refer to the set\_quantity method which will read .pts and .csv files into \ANUGA using memory blocking allowing large files to be used. 3865 3870 \end{classdesc} 3866 3871 … … 4164 4169 \label{mod:neighbourmesh} 4165 4170 4166 \section{\module{abstract\_2d\_finite\_volumes.domain}  Generic module for 2D triangular domains for finitevolume computations of conservation laws} 4171 \section{\module{abstract\_2d\_finite\_volumes.domain}} 4172 Generic module for 2D triangular domains for finitevolume computations of conservation laws 4167 4173 \declaremodule{}{domain} 4168 4174 \label{mod:domain} … … 4194 4200 4195 4201 4196 \section{\module{shallow\_water}  2D triangular domains for finitevolume 4197 computations of the shallow water wave equation. This module contains a specialisation 4198 of class Domain from module domain.py consisting of methods specific to the Shallow Water 4202 \section{\module{shallow\_water}} 4203 2D triangular domains for finitevolume 4204 computations of the shallow water wave equation. 4205 This module contains a specialisation of class Domain from module domain.py consisting of methods specific to the Shallow Water 4199 4206 Wave Equation 4200 }4201 4207 \declaremodule[shallowwater]{}{shallow\_water} 4202 4208 \label{mod:shallowwater} … … 4287 4293 quantities \code{stage}, \code{xmomentum} and \code{ymomentum} at a given point in time 4288 4294 and space as a triplet. To access e.g.\ \code{stage} one must specify element 0 of the 4289 triplet returned by file\_function .4295 triplet returned by file\_function, to access \code{xmomentum} one must specify element 1 of the triplet etc. 4290 4296 4291 4297 \subsubsection{Which diagnostics are available to troubleshoot a simulation?} … … 4300 4306 data is often sparse, or nonexistent. 4301 4307 4308 Note that onshore DEMS can be much finer as the underlying datasets from which they 4309 are created often contain several datapoints per m$^2$. 4310 It may be necessary to thin out the data so that it can be imported 4311 without exceeding available memory. One tool available on the net is called 'decimate'. %FIXME: (Need reference?). 4312 4313 4302 4314 \subsubsection{What sort of mesh resolution should I use?} 4303 4315 The mesh resolution should be commensurate with your DEM  it does not make sense to put in place a mesh which is finer than your DEM. As an example, 4304 4316 if your DEM is on a 25m grid, then the cell resolution should be of the order of 315$m^2$ (this represents half the area of the square grid). Ideally, 4305 4317 you need a fine mesh over regions where the DEM changes rapidly, and other areas of significant interest, such as the coast. 4306 If meshes are too coarse, discretisation errors in both stage and momentum may lead to un physicalresults. All studies should include sensitivity and convergence studies based on different resolutions.4318 If meshes are too coarse, discretisation errors in both stage and momentum may lead to unrealistic results. All studies should include sensitivity and convergence studies based on different resolutions. 4307 4319 4308 4320
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