Using the Flushing Scheduler

Create a flushing simulation

The Flushing Scheduler provides an interactive design view to support the design and evaluation of the schedule. To use the scheduler interactively, a flushing simulation (referencing the network and control to which the schedule is to be applied) must first be set up.

A flushing schedule can be applied only to a checked in network and control data.  Ensure that all flushing points are present as basic nodes or as hydrant nodes in the network.

To set up a flushing schedule for interactive design use:

1. Create a Flushing Schedule object.
2. Create a run of Run Type Flushing. (See About flushing simulations for more details.)
• In the Flushing Options dialog, select the Flushing Schedule object created in Step 1.
• Select the network, control data, and demand diagram to be used by the run.
• Save the run and close the Schedule Hydraulic Run view.
3. Right-click the Flushing Schedule object created in Step 1 and select Open from the context menu to open the Flushing Scheduler.
• On the Simulations page of the scheduler, select the simulation created in step 2 as the Flushing Simulation.

Feedback will now be available on the minimum velocity in pipes being flushed, the number of times water in a flushed pipe is refreshed, and total flush volume. Duration of a flushing action can also be calculated.

To enable feedback on velocity fluctuation problems, a Base Simulation should also be specified:

• Run a normal simulation that covers the dates and times of the flushing schedule actions to provide the results that the flushing simulation results will be compared against.
• Select this normal simulation as the Base Simulation on the Simulations page of the editor.

Define flushing and hydrant criteria

Flushing criteria are used to evaluate the effectiveness of flushing actions, to apply a limit to the water used in flushing, and to calculate and check action timings in the flushing schedule. Flushing criteria are defined on the Criteria & Hydrants page of the Flushing Scheduler. The editor provides default values.

Flushing points for each action can be basic nodes or hydrant nodes, but all flushing points are treated as hydrant nodes by the flushing simulation. The Hydrant Criteria section on the Criteria & Hydrants page is used to define the hydrant parameters to be used at flushing points. Any number of hydrant types can be specified. The hydrant type is associated with a flushing point on the Schedule page.

Create and edit the schedule

Once base simulations have been selected and criteria have been set, the flushing actions can be created and edited.

On the Schedule page of the Flushing Scheduler:

1. Enter an action name and date/time in the Actions grid.
2. Select the newly created action and enter details in the Selected Action tabs:
• Define the pipes to be flushed:

  Use the Pick Pipe button on the Pipes Flushed tab to select the pipes on the GeoPlan that are to be flushed by the currently selected action.

• Define the flushing points:

  Use the Pick Node button on the Flushing Points tab to select the nodes at which flushing is to occur.

• Define the valves to be closed and opened:

  Use the Pick Pipe button on the Close tab and Open tab to define which valves are to be opened and closed for the currently selected action.

3. Use the Trace, Validate, Update, and Isolate buttons to provide feedback on the currently selected action.

Open a flushing schedule workbook

The schedule can be opened in workbook format.

To open a workbook of the schedule:

1. Right-click the Flushing Schedule object in the Model Group window and select Open As from the context menu.
2. In the Select Format dialog (a multiple selection dialog) select the Workbook option.

   A workbook of the schedule will be displayed, with each scheduled action on a separate page.

3. Use the Action arrow buttons at the top right of the workbook to scroll through the actions.

   Some fields in the workbook can be edited.

   You can save the workbook to a location of your choice by selecting Ctrl + S. Alternatively, when you go to close the workbook view, you are asked whether you want to save your changes.

When the flushing simulation has been run, the required flow rate at each step and the length of time for which the flow must be maintained will be displayed in the workbook.

The After period of and at flow fields can be used to specify a reduced flushing flow to be used after a period of time, therefore saving water. For example: a run of pipes to be flushed is composed of a large diameter pipe followed by a smaller diameter pipe. The larger diameter pipe needs to be flushed for four minutes, the smaller pipe for five minutes. The After period of and at flow fields can be used to specify a reduced flow after four minutes as less flow is needed in the smaller pipe to achieve the required flushing speed.

Note: The values for the After period of and at flow fields are not calculated by the Flushing Scheduler, but can be manually edited in the workbook.