User:Rzzzwilson/ANUGA Hydro

ANUGA Hydro (pronounced /ɘnuːɡɘ haɪdroʊ/) is a free and open source hydrodynamic modelling tool which simulates the effect of riverine flooding, storm surges and tsunamis. It is being developed by Geoscience Australia (GA) and the Australian National University (ANU). The ANUGA name without qualification is used informally to mean the ANUGA Hydro tool.

The ANUGA Modelling Tool

ANUGA uses a Finite volume method to solve the Shallow water equations. The study area is represented by a mesh of triangular cells. By solving the governing equation within each cell, water depth and horizontal momentum are tracked over time. This means it is suitable for simulating water flow onto a beach or dry land around structures such as buildings. ANUGA is also capable of modelling hydraulic jumps due to the ability of the finite volume method to accommodate discontinuities in the solution.

To set up an ANUGA modelling scenario the user specifies the geometry (bathymetry and topography), the initial water level, boundary conditions such as tide, and any forcing terms that may drive the system such as rainfall, water abstraction, wind stress or atmospheric pressure gradients. Gravity and frictional resistance from the different terrains in the model are represented by predefined forcing terms.

Most of ANUGA is written in the Python programming language. Computationally intensive components are written in the C programming language which works directly with NumPy structures.

ANUGA viewer

The ANUGA Viewer is a graphical 3D rendering program suitable for animating the output files from the ANUGA tool.

• 
  The ANUGA viewer showing a simulated flood

GAI - Graphical ANUGA Interface

GAI is a Geographic information system front end to ANUGA which allows convenient and visual tools for setting up hydrodynamic models. GAI depends on ANUGA to run the models created by GAI.

Restrictions and Limitations

Although a powerful and flexible tool for hydrodynamic modelling, ANUGA has a number of limitations that users should be aware of:

• The mathematical model is the two dimensional shallow water wave equation, which cannot resolve vertical convection and consequently cannot model breaking waves or three dimensional turbulence.
• All spatial coordinates are assumed to be in the Universal Transverse Mercator coordinate system (UTM). ANUGA is therefore not suitable for modelling flows in areas larger than one UTM zone (6 degrees wide).
• Frictional resistance is implemented using the Manning formula, but ANUGA has not yet been fully validated in regard to bottom roughness.

Who uses ANUGA

• Geoscience Australia
• Australian National University
• Fire and Emergency Services of Western Australia

What has ANUGA been used for

• ??

Awards

ANUGA has been used to understand tsunami risk to the Western Australia coastline and the results of this work are being utilised by emergency managers and the Department for Planning and Infrastructure in Western Australia. In 2007 this work received the Asia-Pacific Spatial Excellence Award and the Emergency Management Australia Safer Communities Award.