[chripasch]

Hello again, a second question arised.

In the attachment you can find a sceenshot. It is nothing more than a channel which has a part with a steep bed slope of about 20%. The whole file is imported as stl-file. As you can see in the attachment, the are with the steep slope is favorized like steppes. I tried a lot but could not fix / explain it.

Additional information: grid lines are parallel to the surfaces (=bed of channel) upstream and downstream the steep part.

Thanks a lot!

[JBurnham]

The steps are caused by plotting the isosurface in 3-D. They are not really there. You can check this by plotting in 2-D. Pick a slice along the slope and look at it from the Anaylze > 2-D tab. I think you'll see a much smoother surface. Did it work?

[chripasch]

Hello Jeff

Yep, that is true. In the 2D view it looks way better.
Can I assume that the results plotted in the 3D analyze view should always be doubted (e.g. no excess shear stress at the bottom of a sloped flume) ?

Best regards

[JBurnham]

Yes. 3-D plots are for showing for informational purposes, but the process of laying out the iso-surface and wrapping it around the solids and fluid surfaces is not precise. High-precision iso-surfaces would require very heavy resource utilization, and could break most desktop computers when the cell count gets very large (in the millions). So don't trust 3-D plots completely. 2-D and Text Output are the way to go for numerical accuracy.