About surge protection devices and output fields

Step-by-step guide

InfoSurge Pro can accommodate many commonly used surge protection devices (SPDs), including open surge tanks, closed surge tanks, and several types of valves.

In a surge analysis, SPDs are placed on a junction. A junction with an SPD should have only one pipe connected to each side. Some attributes used in SPDs can be calculated with the Model Explorer Auxiliary Calculators.

The Resistance Calculator can be especially helpful when resistance values are required. Almost all SPDs have inflow and outflow resistances, representing the resistance into and out of the pipe network, respectively.

To install an SPD:

1. On the map, select a junction.
2. From the Model Explorer toolbar, click Surge Protection Device.
3. In the Surge Protection Device Data dialog box, expand the Device Type drop-down and select the type of SPD to create.

Note that if a junction node is selected, but the Surge Protection Device button is disabled, a demand change curve has already been defined for it.

To change a node to an SPD

4. With the junction node selected on the map, in the Model Explorer toolbar, click Demand Change.
5. In the Junction Demand Change Data dialog box, click Purge.

There are several output fields for SPDs, representing things like pipeline pressure, air volume, and flow measured at specific points in the network.

• Inlet Pressure is the pipeline pressure at a node with an SPD assigned to it.
• Outlet Pressure is the pressure measured at an SPD.
• Side 1 Flow is flow measured from upstream.
• Side 2 Flow is flow to downstream.
• External Flow is flow to an SPD.
• External Volume is the air volume of an SPD.