overflow grate
overflow grate
(OP)
I am modelling a pond (pre-existing) and was wondering about the best way to model my outlet device. Like many structures I see, this one has a concrete riser with a couple of small holes drilled in the sides and big hole on top which has been fitted with a grate, much like you would see on a catch basin.
Should I model the grate as one big orifice or rows and collumns of small holes? How much difference will it make? As I mentioned, I am more evaluating an existing system, so sometimes the information I get is somewhat limited.
Thank you!
Should I model the grate as one big orifice or rows and collumns of small holes? How much difference will it make? As I mentioned, I am more evaluating an existing system, so sometimes the information I get is somewhat limited.
Thank you!





RE: overflow grate
For the top of the riser, I suggest you compare the two scenarios to see how much they differ. For most spillways (including the top of a riser), a fairly large change in the discharge coefficient will have a relatively minor effect on the peak elevation and disccharge. But you should test this to be sure.
Useful tips: You can disable an existing outlet without deleting it by setting the discharge multiplier to zero. Or you can use Control-Drag to make a copy of the entire node for testing.