The latest news on development work for 12d Model 10 and macros.
12d to Tuflow gives seamless 2d flood modelling
More than a year in development, after considerable technical liaison, and enhancements to both 12d Model and Tuflow, the two packages now work together seamlessly. You can set up and run your TUFLOW project inside 12d Model, and use 12d’s Visualisation tools to view results.
Traditionally used for flood models in large catchments, the ease of use of TUFLOW inside 12d Model means that it is now available for highway works and land development projects.
Determining the direction of flow through roundabouts and intersections is a complicated business, and virtually impossible using traditional cross section methods. This is particularly important when the momentum of the water around corners needs to be considered.
12d Model’s ‘Road Flow’ program was written to allow highway designers access to these tools. We’ve found during Beta testing that it has become a favourite among TUFLOW modellers for the initial setup of TUFLOW projects.
How does 2d flood modelling work? To quote Rob Graham – 12d Programmer and Trainer – you have to start by thinking of the ground as a tilted ice cube tray – with no ice. Water arrives in one cell (cube) and spills over the side into the next cell. And so on. The direction that water flows will depend on the height of water in the adjacent cells, so the flow direction will change as more water arrives. This is ‘2d’ modelling.
EXDS has written a converter that will take an MX input file (major option Survey) and convert the data into a 12d Model field file. All the original lines in the input file are brought across to 12d Model as comments, and all RMS metadata is preserved.
Stormwater pit inlet blockage method
12d Solutions has an additional method to model the way that blockage factors are used for pit inlet capacities in major events. The method described by Australian Rainfall & Runoff simply bypasses 20% of the approach flow (for ongrade pits). This means that for very low flows in major events, that there will always be bypass, no matter how large an intake structure you built.
The new method applies a factor to both the approach and captured values, effectively changing the rating curve for the pit for major events, a technique that is more in line with industry practise in Australia. At present it is available for Rational Analysis/Design, and is set via an environment variable. We are expecting that we will soon see a tickbox on the DNE, and that the method will be extended to Dynamic Drainage.