Why do you need Advanced Valve Control?
Pressure Reducing Valves (PRV) and Pressure Sustaining Valves (PSV) are widely used in water models to separate pressure zones and avoid extremely high and low pressures within a water distribution network. As hydraulic conditions in the water distribution network are highly dynamic, many control valves are designed to be able to automatically adjust their opening based on the system demand or the pressure at a remote location. Therefore, InfoWater provides two advanced modeling options for PRV/PSV to meet the above modeling needs. One is to control PRV/PSV based on a curve that describes how the pressure setting changes with flow; the other is to control PRV/PSV based on a remote junction. The following uses PRV as an example and shows how to implement both control options within InfoWater.
Usually the flow through a PRV does not affect or control the PRV’s pressure setting. In Figure 1, we can see that the PRV’s downstream pressure remains at 50 psi (i.e., PRV pressure setting) through time.
1. Control Based on Curve
Select a PRV, click the Control button to bring up the Simple Control dialog, choose the Curve option, specify a curve that shows the relationship between pressure setting and flow, and press the Create button (see Figure 2).
The pressure setting of the PRV varies with time as a response to the flow change (See Figure 3).
2. Control Based on Remote Junction…
Select a PRV, click the Remote Valve Control button to bring up the dialog, select a remote junction from map, specify a pressure setting that applies at the remote junction, and pressure the Create button (see Figure 4)
Run the model, and create a graph that shows the pressure for both the PRV and the remote junction. As we can see in Figure 5, the downstream pressure of the PRV varies while the remote junction pressure stays constant.