Gutter flow and grated inlets efficiencies based upon FHWA HEC-12 have always been accepted in my experience. HEC-12 will cover on-grade and sumped/sag inlets. This manual is available for free download, and I understand there may be a free software that goes with it. But it is pretty easy to write a spreadsheet based on HEC-12.
What type of inlet? If you are using a cast grate, the foundry will have pass flow tests available for your use. Often, they test the grate at different slopes, so the value you seek may be available.
An open throat inlet. Yes I have some of the flow tests from the foundry on grate inlet capacities. I was just wondering how to model the by-pass flow on an open throat inlet. Inlets will handel X ammount of flow the rest will bypass. Modeling the bypass is where I'm having trouble.
You can define a LINK. On the Advanced tab of the link dialog, there is the option for a Flow Threshold. This allows one to split primary and secondary flow based on a known flow rate.
You can define a LINK. On the Advanced tab of the link dialog, there is the option for a Flow Threshold. This allows one to split primary and secondary flow based on a known flow rate.
I am not sure if this is referring to HydroCad?
Please elaborate.
Yes, my response was referring to HydroCad. I am assuming that is what hargy is asking about. Modeling the bypass in Hydrocad. It sounds as if he has already calculated the caputre rate and bypass rate and just want to know how to split this in Hydrocad.