How did I set two kind of slope in channel ?
 

Dear Experts :

If I want to set a slope in channel. I can set gravity component in the X-direction. But I will set two kind of slope now. Besides uses Auto CAD to construct the slope. Did there have any methods to solve?

Another question. If I construct a Geometric model. On side wall's boundary condition whether to need to set "wall boundary"?

Thanks your help!

Re: How did I set two kind of slope in channel ?
 

What do you mean you will have two slopes? Will they be in different directions or just different parts of the geometry?

The main difference between a wall and a symmetry boundary is there is no friction at the symmetry boundary. So if you have heat applied to the wall or if you are interested in viscous stress along the wall then you would use the wall boundary.

Re: How did I set two kind of slope in channel ?
 

Thanks MC~

Yes, I mean that have a channel but there have two kind of slopes(that is upstream slope is 1 degree downstream slope is 5 degree). How did I set two kind of slopes, I don't want to use Auto CAD to draw slopes of channel.

Thanks your help!

Re: How did I set two kind of slope in channel ?
 

I think either way you will have to use AutoCAD unless your channel is simple geometry then you could create it in FLOW-3D and rotate it to the angled slope. :)

Re: How did I set two kind of slope in channel ?
 

Very thanks your help, MC.

Re: How did I set two kind of slope in channel ?
 

There is another problem with slope channel - mesh roughness (as we call it). If you rotate your channel in AutoCAD you will get roughness due to vertical orthogonal cubic mesh. That is the problem. I used component of gravity.

Regards.

how to incorporate a single slope using component of gravity ? (I want to give 1:500 slope for simple rectangular open channel) I tried with autocad but results are not accurate. plz help

Hello. Calculate the channel slope. Using the formula, slope equals the change in elevation divided by ground distance.

krunker

In Flow 3D, geometry file is one of the main inputs. Remember

TEL = z + h + v2/2g

'z' comes from geometry. Once 'z' is disturbed, results will be incorrect no matter how realistic they look.

Remember that for initialisation by elevation, it will be applied in the Z direction (in case you change the gravity vector to something else).