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Rainfall Infiltration Boundary Condition (COMSOL 4.0)

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I am doing groundwater modeling which need to specify this boundary condition for the surface.
Here I have 1-year rainfall data, including precipitation rate and direct surface runoff in each hours.

In order to specify, I defined an interpolation function and imported hourly infiltration rate (text file) into it. However, because when it rains, water gradually accummulates at the surface and creates ponds (in my case, ponded height = 0.01 m). So the rainfall infiltration boundary conditions involve switching between Dirichlet and Neumann boundary conditions. I got stuck at this point, haven't found good way to define the boundary conditions.
Anyone can help me?

4 Replies Last Post 17 nov 2011, 00:35 GMT-5

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Posted: 1 decade ago 20 mar 2011, 14:45 GMT-4
Oh, I've just tried out with the Pervious Layer boundary condition and Inward boundary condition to specify the rainfall infiltration at the surface. In particular, I defined an interpolation function to express the infiltration rate in every hours. Then I filled in the inflow velocity box (indise Inward Boundary condition) with the interpolation function created.
Is it the correct way? Waiting for your kind help. Thank you!
Oh, I've just tried out with the Pervious Layer boundary condition and Inward boundary condition to specify the rainfall infiltration at the surface. In particular, I defined an interpolation function to express the infiltration rate in every hours. Then I filled in the inflow velocity box (indise Inward Boundary condition) with the interpolation function created. Is it the correct way? Waiting for your kind help. Thank you!

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Posted: 1 decade ago 21 mar 2011, 11:03 GMT-4
Sorry to raise this topic again, but could someone help me? Thank you!
Sorry to raise this topic again, but could someone help me? Thank you!

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Posted: 1 decade ago 9 nov 2011, 01:00 GMT-5
Hi Charles!

I am also looking at the same problem! I dont know, but if i come accross i will post it.

thanks
Hi Charles! I am also looking at the same problem! I dont know, but if i come accross i will post it. thanks

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Posted: 1 decade ago 17 nov 2011, 00:35 GMT-5
hey i found this might be useful

www.stanford.edu/dept/cee/faculty/freyberg/ChuiFreyberg.pdf
hey i found this might be useful http://www.stanford.edu/dept/cee/faculty/freyberg/ChuiFreyberg.pdf

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