HEC-RAS Result Export for every Time Step and Cross Section

[Anonymous]

Hi all,

I am using HEC-RAS for tidal-influenced river analysis (unsteady). The model has about 500 cross sections. For further analysis in post-processing, I have to export the simulation results of water level, velocity and flow (discharge) for every cross section and avery single time step, which is 2 minutes. The overall simulation period is about 14 days.

I so far could not find a way to semi-automatically export my dat into an ascii file:
– HEC-DSSVue does not store the velocities and uses a strange output format
– HEC-RAS (Summary output tables by profiles) crashes even for one-day-simulation data, I guess due to the wuite large amount of data.

For generating the latter output data, I used the post processor of the unsteady flow analysis, which took about 2:30 hours (!) and produces a 6GB .Oxx file. I guess, this is too much for HEC-RAS.

Any hints on how to get the data out of HEC???

Arne

[Anonymous]

You might try the Computation Level Output. From the Unsteady run editor, go to Options > Output Options > Computation Level Output and click velocity on and then run the model.

Afterwards, from the main RAS window, select View and then you can select Unsteady Spatial plot or Unsteady Flow Time series plot. If you go to Table, you could copy and paste. You can look at all the water surfaces, flows, and velocities at all cross sections for one point in time or all of the values for a single cross section at all points in time. So to extract everything by hand would be a bit tedious.

I don’t know much about it, but using the RASController feature you might be able to automate this. This web site has a forum dedicated to this.

[Anonymous]

If the output files are getting too big, you could break your run up by writing out restart files. For instance, do a 2 day run and write out a restart file. Then do the next two days using the restart file.

[Anonymous]

Hi Jarvus

Thanks for your feedback. I also thought about using the Detailed Output, but as you said, it is not possible to display and export all the data in one step. I’m not familiar with the controller.

Therefore, I now use the detailed log output for debuggin, which writes W, Q and V at every cross section (has to be defined under Stage and Flow Output Locations) and time step – exactly what I was looking for.

Getting the data into Matlab in a sorted order is however “under contruction” right now, as the format is sometimes a bit unclear.

[Rodolfo Dornelas]

You can also look at the results in the HDF format, see the 2D Modeling User’s Manual.

[Author]

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