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Branch External Upstream & Downstream Head File

Wed, 03/25/2009 - 1:40am — Huyen
hi, I don't understand the purpose of the "Branch External Upstream Head Files" and "Branch External Downstream Head Files" which should be given in the model and what is the difference between the "Branch External Upstream Head Files" and the "Files of Branch"? May anybody help me? Thank you. Huyen
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Water Quality
Fri, 03/27/2009 - 11:33am — chris

Hello Huyen, The only difference is that "Branch External Upstream Head Files" correspond to head boundary condition located at the upstream (lower segment number) end of a branch and the "branch external downstream head files" correspond to a head BC at the downstream end (with a higher segment number) of a branch. chris
Mon, 03/30/2009 - 7:26am — Huyen

Thank you Chris for the information. I have not yet undertood why we need use the Branch External Upstream Head Boundary Condition and Branch External Downtream Head Boundary Condition, I mean the purpose on using this Files. We use the Branch File (inflow, temperature, constituent) for the Input into the first Branch. Why do we need the Branch External Upstream Head Boundary Condition? And how about the purpose on using the Branch External Downtream Head Boundary Condition? Thank you in advance
Wed, 04/01/2009 - 6:14pm — chris

Huyen, If you have flow boundary condition at the end of a branch, you don't need a head boundary condition. A branch head boundary condition is used if you are using water surface elevation rather than flow rate as the boundary condition. Hope this helps, chris