Question about inlet design using HEC-22
Question about inlet design using HEC-22
(OP)
Hello everybody. I'm designing some inlets using the procedures in HEC-22. I'm using the FHWA Hydraulic Toolbox. In some inlets, this message is shown: "The approach velocitiy is greater than the splash-over velocity. Please consider a longer grate or a different configuration." I've checked the HEC-22 and they say that if this happens the frontal interception capacity is reduced. (Pag 4-41). The bypass flow will be added to the next inlet, so this inlet doesn't need to intercept all the flow. My question is, do I need to change the inlet dimensions to reduce the approach velocity? Or can I use these results with the approach velocity greater than the splash-over velocity? Thanks for your help.





RE: Question about inlet design using HEC-22
Without redesigning the roadway, there is no way to "reduce the approach velocity" other than reducing the flow (reduced inlet spacing.)
The "different configuration" that would make sense might be: a different grate (better splashover characteristics), a longer grate, or reducing the spacing between inlets. The message seems to be more of a warning than an error.
RE: Question about inlet design using HEC-22