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Mummputz September 19, 2012 09:22

SSIIM 2, vertical elevation of the water surface, transient water flow parameters
I want to simulate a step- pool ramp with ssiim2. However, the measured vertical elevations of the water surface don't match with the simulated ones- while the measured heights increase lightly where the stone bars are, there is no influence at all of the stone bars on the water heights in the simulation and the water surface is totally smooth. I increased the stone bars and their roughness, but this doens't help.

This is why I wanted to introduce transient water flow parameters by using the F 33 data set and a gravity- algorithm by using the F36 15 data set. However- this doesn't work and the solution never converges!!! I'm very much beginner with all of that and it would be very useful to have an example where these data sets do work. On the norvegian ssiim- homepage, there is such an example, but it doesn't work with the currently downloadable ssiim2-version. If anybody could provide me an example- I would be so glad- thank you!!

qinjie1629 October 22, 2012 00:35

Maybe you can post your control and unstruc file, I can run it to find out what is the problem.

Mummputz October 23, 2012 08:09

control and unstruc file
1 Attachment(s)
thank u, so nice!!- attached the control and unstruc files
all the best!

qinjie1629 October 23, 2012 11:39

I think the most possible reason is attributed to the mesh quality. When you open the SSIIM2, choose 'View' ->'Profile I', you can find that the mesh is too thick in vertical direction and too sparse in longtitudinal direction. Generally, individual grids should close to 'square' not 'rectangular' shown in your mesh. You can try to rebuilt the mesh and run it again.

Mummputz October 24, 2012 02:54

2 Attachment(s)
I've already tried that before- it didn't work, that's why I tried to create a mesh as simple as possible

I can't attach the unstruc file, bcse it's too big, that's why I send u the control and koordina file

qinjie1629 October 24, 2012 09:05

1 Attachment(s)
I tried to run the case you post for the first time by simply modifying several parameters and the resutl is attached. The deformation of water surface around the triangle can be observed. The flow discharge is 4. You can change the discharge from 1 to 5 to see the variation of flow surface. I am not sure whether this is what your expected result.

I found the Koordina file doese not like a really topography of step-pool, so did the fisrt unstruc file. So, how did you specified the flow discharge and flow depth in the control file. Different flow discharge and flow depth will affect the flow depth near the obstacle significantly.

mona nemati November 18, 2012 14:39

i have many problem with geodata file in ssiim2,when i involve a geodata file in path ssiim2,for see the points cliking "view> GridEditor> Geodata point"
but any point i can't see,until click the legend,then i see cell number in ssiim,but i dont know how make grid with geodatapoint,is there anyone help me here?

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