Results analyse -free surface model

antonio · February 2, 2010, 10:36

Hi all

.

I`m following the free-surface tutorial. As my domain has a geometry that has translational periodicity I have used a domain interface (with a pressure change of -1.044664 Pa). The dimensions of the domain are 49.267 mm (longitudinal direction) 160mm (height of the domain) and 800 (it`s the width of the channel). I have a rough bed (with an inclination of 8.9*10^-4)formed by the contour of triangles (with an height of 4.61 mm). The initial expressions that I have used are the same as the tutorial (as I want to have an uniform regime I set a UpH and DownH to 0.12 m) and I have used the same boundaries presented in the tutorial (inlet, outlet opening and wall). I have not used a symmetry boundary because the mesh is not symmetric. Observing the results in CFD-Post I have the feeling that I don`t have an uniform regime. When I create an isosurface (water volume fraction of 0.06) the free surface is very irregular and the green line that should appear is not continuous. I also have water for higher water volume fractions...Should I create a larger domain to have an uniform regime?

Best Regards

ghorrocks · February 2, 2010, 17:02

Can you post some images of you geometry, mesh and the results you are getting?

antonio · February 3, 2010, 05:23

Good morning all

Dear Ghorrocks. Sure I can post some images. Can you explain me how to do that? I`m having some difficulties.

Regards

ghorrocks · February 4, 2010, 05:04

My guess is the button labelled "Insert Image" will do it. But I am just guessing there.

antonio · February 5, 2010, 12:35

Hi there

.

I have already did what you mentioned but I did not have success.

However, I think my main problem is solved. I have created a monitor point and I have seen the water volume fraction evaluation along the simulation and it seems that this variable is constant when I achieve a significant number of iterations so I suppose I have an uniform regime...

Best Regards

February 2, 2010, 10:36	Results analyse -free surface model	#1
antonio Senior Member Join Date: Jan 2010 Posts: 110 Rep Power: 16	Hi all. I`m following the free-surface tutorial. As my domain has a geometry that has translational periodicity I have used a domain interface (with a pressure change of -1.044664 Pa). The dimensions of the domain are 49.267 mm (longitudinal direction) 160mm (height of the domain) and 800 (it`s the width of the channel). I have a rough bed (with an inclination of 8.9*10^-4)formed by the contour of triangles (with an height of 4.61 mm). The initial expressions that I have used are the same as the tutorial (as I want to have an uniform regime I set a UpH and DownH to 0.12 m) and I have used the same boundaries presented in the tutorial (inlet, outlet opening and wall). I have not used a symmetry boundary because the mesh is not symmetric. Observing the results in CFD-Post I have the feeling that I don`t have an uniform regime. When I create an isosurface (water volume fraction of 0.06) the free surface is very irregular and the green line that should appear is not continuous. I also have water for higher water volume fractions...Should I create a larger domain to have an uniform regime? Best Regards

February 5, 2010, 12:35		#5
antonio Senior Member Join Date: Jan 2010 Posts: 110 Rep Power: 16	Hi there. I have already did what you mentioned but I did not have success. However, I think my main problem is solved. I have created a monitor point and I have seen the water volume fraction evaluation along the simulation and it seems that this variable is constant when I achieve a significant number of iterations so I suppose I have an uniform regime... Best Regards

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February 2, 2010, 17:02		#2
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,703 Rep Power: 143	Can you post some images of you geometry, mesh and the results you are getting?

February 3, 2010, 05:23		#3
antonio Senior Member Join Date: Jan 2010 Posts: 110 Rep Power: 16	Good morning all Dear Ghorrocks. Sure I can post some images. Can you explain me how to do that? I`m having some difficulties. Regards

February 4, 2010, 05:04		#4
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,703 Rep Power: 143	My guess is the button labelled "Insert Image" will do it. But I am just guessing there.