I have already modeled my drainage basins and detention pond. Can you explain how to use the special outlet device to define a pump rating curve? I have the outlet modeled as a culvert with free discharge.
On the outlet device screen, double-click a blank line and select "Special Outlet". You can then enter a rating curve for the pump. This could be as simple as 2 or 3 dicharge-vs-head values. You can enter elevation or head in the table. If you enter head, set the invert elevation to the point where the pump will come on.
I found this post after I attempted to model a pump myself. In my case, I used an exfiltration outflow with the pump's discharge rate. What would the difference in the models be between what you suggest and my model?
Great idea! Using an exfiltration outlet is a good option when the pump rate is constant. It actually saves the hassle of entering a multi-point stage-dischrage curve as required by the special outlet. Just enter the constant CFS rate, and set the invert elevation to the level where the pump will turn on.
To avoid confusion, be sure to change the device name from "Exfiltration" to something more appropriate, such as "Pump". Since an exfiltration outlflow is normally discarded, you will probably want to change the device routing to Primary or Secondary, depending on how the flow is being combined with other outlets, such as an overflow.
