Simulating drain down and recharge

00:04

In info

00:04

works.

00:04

WS pro the drain down and recharge simulation

00:08

options in the run schedule can improve the

00:10

model accuracy for a situation in which a

00:12

network loses pressure and pressure is later recharged.

00:17

This simulation can highlight the locations of the first and last customers

00:22

to lose pressure and how long it could take to regain it

00:26

in this exercise. Part of a small network is isolated for a water quality issue

00:32

in the model group window under the drain down model group click and

00:36

drag the drain town network into the workspace to open the GEO plan.

00:41

This small network is supplied by a simple fixed

00:44

head node representing a pumping station to the east

00:47

to simulate drain down.

00:49

You will close an isolation valve just downstream of

00:51

the pumping station to see the effect on the network

00:55

first. Create a new scenario by clicking the create scenario button in the toolbar.

01:01

In the new scenario, name field type in the name isolation,

01:06

click. OK.

01:07

Then zoom into the area of the

01:09

network immediately downstream of the pumping station.

01:13

Double click the valve in the upper part of the T

01:15

junction with the asset ID 205301 to open its properties.

01:22

Scroll down in the valve object properties window and under valve control,

01:26

find the mode id field.

01:29

It is currently set as a TV,

01:31

a throttled valve which does not change during a simulation.

01:35

You need to change it to a time controlled valve T CV.

01:39

So you can open and close it during the simulation to model a temporary shutdown,

01:44

expand the dropdown and select T CV.

01:48

You now have the option to edit the profiles field.

01:52

Click the more button with the ellipsis to open a dialogue where

01:55

you can edit the date and time of the valve opening and closing

01:59

in the table.

02:00

In the date and time column,

02:02

either expand the drop down to set the

02:04

following dates and times or type them in manually

02:08

in the first row. March 1st 2023 at midnight

02:13

in the second row, March 1st 2023 at six AM

02:18

and in the third row, March 1st 2023 at seven PM

02:24

in the opening percentage column type in the following values

02:28

in the first row, 100

02:31

in the second row zero

02:33

and in the third row 100

02:36

this means the valve is set to be fully open at midnight,

02:40

close at six AM, then open again at seven PM.

02:44

Click, OK.

02:47

In the toolbar, click save data to commit the changes you just made to the database.

02:52

Click OK? In both notifications that follow

02:56

then, right click the drain down model group and create a new run group and run

03:04

in the schedule. Hydraulic run dialogue in the title field.

03:07

Enter the name isolation base.

03:10

Enable the experimental option

03:13

with the required items.

03:14

Tab open click and drag the drain town network to the network pa in the dialogue.

03:20

In this example,

03:21

the control and demand diagram pans populate automatically because

03:25

they were previously associated with the drain town network.

03:29

Next, open the scenarios, tab

03:32

disable the base option and then enable isolation,

03:36

click save and then run

03:40

info works. WS pro does not simulate draind down by default.

03:43

So the results of this run will serve as a before snapshot for comparison later,

03:50

once the run is finished, click and drag the results to open them in the GEO plan

03:55

in the tools, toolbar,

03:56

click the graph tool and then click any hydrant downstream of the valve.

04:01

In this example, a hydrant with the asset ID 397 884 is selected.

04:08

The graph indicates a total loss in pressure at six AM when

04:12

the valve closes and pressure then returns to normal at seven PM.

04:16

After the valve opens again,

04:19

you can also select any link to view similar effects on flow.

04:24

At this time,

04:25

you have the option to run a query to find

04:27

out how many customers were isolated during this operation.

04:31

Expand the stored query group, then click and drag.

04:34

Select isolated customers to the GEO plan to run it.

04:39

This automatically selects all customers in the network

04:41

who were isolated for longer than one hour.

04:45

In this case,

04:45

every customer highlighted in red downstream of the valve is affected.

04:50

Now run the isolated customer count query.

04:53

A small grid appears in the workspace indicating

04:56

that 230 customers were isolated during the operation

05:01

in the replay toolbar. Click clear results.

05:05

Now you'll run another simulation this time with draind down enabled

05:10

double click the isolation base run to open the schedule,

05:13

hydraulic run dialogue again,

05:15

change the name to isolation, draind down and then click save.

05:21

Note that the new run displays in the model group window

05:25

in the run parameters group box,

05:27

expand the dropdown and select simulation options.

05:31

Then click the options button

05:33

in the simulation options window enable allow drain down and allow recharge,

05:40

close the window. Then click save and run in the dialogue.

05:45

Open the results by clicking and dragging them to the GEO plan

05:50

with the graph tool enabled. Click the same hydrant as you did. After the base run,

05:56

the graph shows that instead of the pressure dropping to zero,

05:59

it stops at a lower value and then gradually decreases until around six PM.

06:04

Repeat this action by graphing any link downstream

06:07

from the valve to see that flow is also

06:09

impacted during the isolation period but is not immediately

06:12

interrupted as it was in the base run.

06:15

Once again,

06:16

run the select isolated customers and isolated customer count queries.

06:21

The select isolated customers query shows far fewer customers are isolated

06:26

for longer than one hour than in the base run.

06:28

Customers not highlighted retain water pressure,

06:31

albeit lower pressure rather than losing it completely.

06:35

The isolated customer count query shows far fewer customers. Only 60.

06:39

In this case are isolated.

06:42

You can also visualize the run results using a long section

06:46

in the tools,

06:47

toolbar enable the trace and select links upstream tool and then find

06:52

the southwestern most point in the network and click to highlight it.

06:56

This runs a trace back to the water source.

06:60

Now from the windows toolbar,

07:02

click the new long section tool to view the

07:04

traced portion of the network as a long section,

07:07

right,

07:08

click the long section window and select

07:10

properties to open the section properties dialogue

07:13

for better visual clarity.

07:15

When viewing the long section disable the option to show min

07:18

max HGL lines.

07:21

Click OK.

07:23

In the long section window,

07:25

the horizontal blue line indicates the pressure level in

07:28

relation to the position within the long section.

07:32

In the replay toolbar,

07:33

click play to step through the simulation

07:35

timeline and observe how the pressure changes at

07:38

six AM when the valve is closed and then gradually decreases until seven PM.

07:44

Portions of the network immediately downstream of

07:46

the isolation lose pressure during this time.

07:49

But areas further downstream, maintain pressure

07:53

at seven PM. The isolation valve reopens and the network is recharged.

Video transcript

00:04

In info

00:04

works.

00:04

WS pro the drain down and recharge simulation

00:08

options in the run schedule can improve the

00:10

model accuracy for a situation in which a

00:12

network loses pressure and pressure is later recharged.

00:17

This simulation can highlight the locations of the first and last customers

00:22

to lose pressure and how long it could take to regain it

00:26

in this exercise. Part of a small network is isolated for a water quality issue

00:32

in the model group window under the drain down model group click and

00:36

drag the drain town network into the workspace to open the GEO plan.

00:41

This small network is supplied by a simple fixed

00:44

head node representing a pumping station to the east

00:47

to simulate drain down.

00:49

You will close an isolation valve just downstream of

00:51

the pumping station to see the effect on the network

00:55

first. Create a new scenario by clicking the create scenario button in the toolbar.

01:01

In the new scenario, name field type in the name isolation,

01:06

click. OK.

01:07

Then zoom into the area of the

01:09

network immediately downstream of the pumping station.

01:13

Double click the valve in the upper part of the T

01:15

junction with the asset ID 205301 to open its properties.

01:22

Scroll down in the valve object properties window and under valve control,

01:26

find the mode id field.

01:29

It is currently set as a TV,

01:31

a throttled valve which does not change during a simulation.

01:35

You need to change it to a time controlled valve T CV.

01:39

So you can open and close it during the simulation to model a temporary shutdown,

01:44

expand the dropdown and select T CV.

01:48

You now have the option to edit the profiles field.

01:52

Click the more button with the ellipsis to open a dialogue where

01:55

you can edit the date and time of the valve opening and closing

01:59

in the table.

02:00

In the date and time column,

02:02

either expand the drop down to set the

02:04

following dates and times or type them in manually

02:08

in the first row. March 1st 2023 at midnight

02:13

in the second row, March 1st 2023 at six AM

02:18

and in the third row, March 1st 2023 at seven PM

02:24

in the opening percentage column type in the following values

02:28

in the first row, 100

02:31

in the second row zero

02:33

and in the third row 100

02:36

this means the valve is set to be fully open at midnight,

02:40

close at six AM, then open again at seven PM.

02:44

Click, OK.

02:47

In the toolbar, click save data to commit the changes you just made to the database.

02:52

Click OK? In both notifications that follow

02:56

then, right click the drain down model group and create a new run group and run

03:04

in the schedule. Hydraulic run dialogue in the title field.

03:07

Enter the name isolation base.

03:10

Enable the experimental option

03:13

with the required items.

03:14

Tab open click and drag the drain town network to the network pa in the dialogue.

03:20

In this example,

03:21

the control and demand diagram pans populate automatically because

03:25

they were previously associated with the drain town network.

03:29

Next, open the scenarios, tab

03:32

disable the base option and then enable isolation,

03:36

click save and then run

03:40

info works. WS pro does not simulate draind down by default.

03:43

So the results of this run will serve as a before snapshot for comparison later,

03:50

once the run is finished, click and drag the results to open them in the GEO plan

03:55

in the tools, toolbar,

03:56

click the graph tool and then click any hydrant downstream of the valve.

04:01

In this example, a hydrant with the asset ID 397 884 is selected.

04:08

The graph indicates a total loss in pressure at six AM when

04:12

the valve closes and pressure then returns to normal at seven PM.

04:16

After the valve opens again,

04:19

you can also select any link to view similar effects on flow.

04:24

At this time,

04:25

you have the option to run a query to find

04:27

out how many customers were isolated during this operation.

04:31

Expand the stored query group, then click and drag.

04:34

Select isolated customers to the GEO plan to run it.

04:39

This automatically selects all customers in the network

04:41

who were isolated for longer than one hour.

04:45

In this case,

04:45

every customer highlighted in red downstream of the valve is affected.

04:50

Now run the isolated customer count query.

04:53

A small grid appears in the workspace indicating

04:56

that 230 customers were isolated during the operation

05:01

in the replay toolbar. Click clear results.

05:05

Now you'll run another simulation this time with draind down enabled

05:10

double click the isolation base run to open the schedule,

05:13

hydraulic run dialogue again,

05:15

change the name to isolation, draind down and then click save.

05:21

Note that the new run displays in the model group window

05:25

in the run parameters group box,

05:27

expand the dropdown and select simulation options.

05:31

Then click the options button

05:33

in the simulation options window enable allow drain down and allow recharge,

05:40

close the window. Then click save and run in the dialogue.

05:45

Open the results by clicking and dragging them to the GEO plan

05:50

with the graph tool enabled. Click the same hydrant as you did. After the base run,

05:56

the graph shows that instead of the pressure dropping to zero,

05:59

it stops at a lower value and then gradually decreases until around six PM.

06:04

Repeat this action by graphing any link downstream

06:07

from the valve to see that flow is also

06:09

impacted during the isolation period but is not immediately

06:12

interrupted as it was in the base run.

06:15

Once again,

06:16

run the select isolated customers and isolated customer count queries.

06:21

The select isolated customers query shows far fewer customers are isolated

06:26

for longer than one hour than in the base run.

06:28

Customers not highlighted retain water pressure,

06:31

albeit lower pressure rather than losing it completely.

06:35

The isolated customer count query shows far fewer customers. Only 60.

06:39

In this case are isolated.

06:42

You can also visualize the run results using a long section

06:46

in the tools,

06:47

toolbar enable the trace and select links upstream tool and then find

06:52

the southwestern most point in the network and click to highlight it.

06:56

This runs a trace back to the water source.

06:60

Now from the windows toolbar,

07:02

click the new long section tool to view the

07:04

traced portion of the network as a long section,

07:07

right,

07:08

click the long section window and select

07:10

properties to open the section properties dialogue

07:13

for better visual clarity.

07:15

When viewing the long section disable the option to show min

07:18

max HGL lines.

07:21

Click OK.

07:23

In the long section window,

07:25

the horizontal blue line indicates the pressure level in

07:28

relation to the position within the long section.

07:32

In the replay toolbar,

07:33

click play to step through the simulation

07:35

timeline and observe how the pressure changes at

07:38

six AM when the valve is closed and then gradually decreases until seven PM.

07:44

Portions of the network immediately downstream of

07:46

the isolation lose pressure during this time.

07:49

But areas further downstream, maintain pressure

07:53

at seven PM. The isolation valve reopens and the network is recharged.

Video quiz

Which of the following types of simulations can reveal the locations of the first and last customers to lose pressure and how long it could take for them to regain it?

(Select one)
Select an answer

1/1 questions left unanswered

Step-by-step Guide

In InfoWorks WS Pro, drain down and recharge simulation options can improve the model accuracy for a situation in which a network loses pressure and is later recharged. A simulation can highlight the first and last customers to lose pressure and how long it may take to regain it. In this exercise, part of a small network is isolated for a water quality issue.

  1. From the Model Group window, under Draindown, drag-and-drop the DrainTown network into the workspace to open the GeoPlan.

This network is supplied by a fixed head node, a pumping station to the East. To simulate drain down, close an isolation valve just downstream of the pumping station.

Start by creating a new scenario:

  1. In the Scenarios toolbar, click the Create Scenario button:
  2. In the New Scenario Name field, enter “Isolation”.
  3. Click OK.

In the InfoWorks WS Pro interface, the Create New Scenario dialog box with the name entered and OK selected, and behind it, the DrainTown GeoPlan open.

Next, select a valve to close:

  1. In the GeoPlan, zoom into the area of the network immediately downstream of the pumping station.
  2. Double-click the valve with asset ID 205301.

In the Valve Object Properties panel, under Valve Control, notice the Mode ID is currently set to THV (a throttled valve), which does not change during a simulation. Change it to a time-controlled valve (TCV), which can open and close to model a temporary shutdown.

  1. Expand the Mode ID drop-down and select TCV.

The Valve Object Properties panel, Valve Control section, with Mode ID highlighted in red and TCV selected in the drop-down; and the GeoPlan zoomed into the selected node, also highlighted in red.

To set the valve to be fully open at midnight, to close at 6 am, and to open again at 7 pm:

  1. In the Profiles field, click the More () button.
  2. In the profile graph window, in the Date & Time column, expand the drop-down and select March 1, 2023.
  3. Leave the time of day set to 00:00:00.
  4. In the Opening (%) column, enter “100”.
  5. In the second row, set the date to March 1, 2023.
  6. Set the time to 06:00:00.
  7. Set the Opening (%) to “0”.
  8. In the third row, set the date to March 1, 2023.
  9. Set the time to 19:00:00.
  10. Set the Opening (%) to “100”.
  11. Click OK.

The Valve window with values entered in the Date & Time and Opening (%) fields, highlighted in red, and OK selected.

  1. Commit the changes to the database.

Now, create a new run:

  1. In the Model Group window, right-click Draindown and select New > Run Group.
  2. In the Run Group dialog box, click OK.
  3. From the Model Group window, right-click the new Run Group and select New > Run.
  4.  In the Schedule Hydraulic Run dialog box, in the Title field, enter the name “IsolationBase”.
  5. Enable the Experimental option.
  6. From the Model Group windows, drag the DrainTown network into the Schedule Hydraulic Run dialog box and drop it into the Network pane.

The path of the DrainTown network from the Model Group window to the Schedule Hydraulic Run dialog box, Network pane, indicated with a dotted red arrow.

In this example, the Control and Demand Diagram panes populate automatically, because they were previously associated with the DrainTown network.

  1. Open the Scenarios tab.
  2. Disable the Base scenario.
  3. Enable Isolation.
  4. Click Save.
  5. Click Run.

The Schedule Hydraulic Run dialog box with options configured for the IsolationBase run and Run selected.

InfoWorks WS Pro does not simulate drain down by default, so the results of this run serve as a “before” snapshot for comparison later.

To graph the results:

  1. Once the run finishes, drag-and-drop the results into the workspace to open the GeoPlan.
  2. In the Tools toolbar, click the Graph button.
  3. Click a hydrant downstream of the valve. In this example, the hydrant with asset ID 397884 is selected.

The graph indicates a total loss in pressure at 6 am when the valve closes, and a return to normal pressure at 7 pm after the valve opens again.

An IsolationBase graph window showing pressure (m) for the hydrant over 24 hours.

  1. Optional: Graph any link to view similar effects on flow.

To identify which customers were isolated during this operation:

  1. In the Model Group window, expand the Stored Query group.
  2. Drag-and-drop the Select Isolated Customers query into the GeoPlan to run it.

In the Model Group window, the Select Isolated Customers query highlighted in red, and in the GeoPlan, the query results highlighted in red.

All network customers isolated longer than an hour appear highlighted in red. In this case, every customer downstream of the valve is affected.

To identify the number of isolated customers:

  1. From the Model Group window, under Stored Query, drag-and-drop the Isolated Customer Count query into the GeoPlan.

A small grid appears, indicating that 230 customers were isolated.

  1. In the Operations toolbar, click Clear selection.

Next, run another simulation, but this time, with drain down enabled:

  1. In the Model Group window, double-click the IsolationBase run.
  2. In the Schedule Hydraulic Run dialog box, change the name to “IsolationDraindown”.
  3. Click Save.

The new run displays in the Model Group window.

  1. In the Schedule Hydraulic Run dialog box, in the lower-left corner, expand the drop-down and select Simulation Options.
  2. Click the Options button.
  3. In the Simulation Options window, enable Allow Drain Down.
  4. Enable Allow Recharge.

In the Schedule Hydraulic Run dialog box, Simulation Options and the Options button highlighted in red; and in the Simulation Options dialog box, Allow Drain Down and Allow Recharge deselected and highlighted in red.

  1. Close the window.
  2. In the Schedule Hydraulic Run dialog box, click Save.
  3. Click Run.

To graph the results of the drain down run:

  1. From the Model Group window, drag-and-drop the results into the GeoPlan.
  2. In the Tools menu, click Graph.
  3. In the GeoPlan, select the same hydrant as in the base run, with asset ID 397884.

An IsolationDraindown graph window showing pressure (m) for the hydrant over 24 hours.

The graph shows that instead of the pressure dropping to zero, it stops at a lower value and then gradually decreases until around 6 pm.

  1. Graph any link downstream from the valve.

An IsolationDraindown graph window showing pressure (m) for a link downstream from the valve over 24 hours.

Notice the flow is impacted during the isolation period but is not immediately interrupted, as in the base run.

  1. Run the Select Isolated Customers query again.
  2. Run the Isolated Customer Count query.

In the IsolationDraindown GeoPlan, results of the Select Isolated Customers highlighted in red, and in a grid window, results of the Isolated Customer Count query highlighted in red.

The Select Isolated Customers query shows far fewer customers isolated for longer than an hour, as compared to the base run. Customers not highlighted retained lower water pressure, rather than losing it completely. The Isolated Customer Count query shows only 60 customers isolated, as compared to 230.

To visualize the run results using a long section:

  1. In the Tools toolbar, select the Trace and select links upstream button.
  2. In the GeoPlan, click to highlight the southwestern-most point in the network and run a trace back to the water source.

In the Tools toolbar, the Trace and select links upstream button highlighted in red, and in the GeoPlan, the southwestern-most point highlighted in red.

  1. In the Windows toolbar, click the New long section button to view the traced portion of the network as a long section.

In the Windows toolbar, New long section selected and called out, and in the GeoPlan, the traced portion of the network highlighted in red.

  1. In the GeoPlan, right-click the long section window and select Properties.
  2. In the Section Properties dialog box, disable Show Min/Max HGL Lines, for better visual clarity when viewing the long section.
  3. Click OK.

The Section Properties dialog box With Show Min/Max HGL Lines deselected and highlighted in red, and OK selected.

In the long section window, the horizontal blue line indicates the pressure level in relation to the position within the long section.

  1. In the Replay toolbar, click Play to step through the simulation timeline.

In the Replay toolbar, the Play button highlighted in red, and in the long section window, the simulation showing a pressure change after the valve is closed.

Notice the pressure changes at 6 am when the valve is closed, and then gradually decreases until 7 pm. Portions of the network immediately downstream of the isolation lose pressure during this time, but areas further downstream maintain pressure. At 7 pm, the isolation valve reopens, and the network is recharged.

Was this information helpful?