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Integrated BIM tools, including Revit, AutoCAD, and Civil 3D
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Transcript
00:04
A design firef flow simulation allows you to add a secondary pressure constraint
00:08
to identify the junction with the lowest pressure within a search range.
00:12
The hydrant available flow calculated in the standard firef
00:15
flow simulation is recalculated based on this critical node.
00:19
So its pressure does not drop below the minimum pressure constraint.
00:22
This new value is called the hydrant design flow
00:26
to begin. Double click the desired project dot APR X file to open
00:30
Agis Pro.
00:32
Once the project starts,
00:33
click the info water pro tab to open the info water pro ribbon
00:38
in the project panel, click initialize
00:42
on the info water pro ribbon in the analysis panel, click run
00:47
in the run manager on the firef flow tab.
00:49
Enable run firef flow on domain only to
00:52
restrict the analysis to the selected domain.
00:57
Also enable design firef flow to add the pressure constraint
01:00
but keep the minimum pressure accuracy and minimum iteration values as they are
01:06
also keep in mind that the minimum pressure is set to 20 psi
01:10
lastly expand the critical node, search range dropdown and select domain nodes.
01:17
Now while simulating a hydrant flowing,
01:19
the software will check the pressures at all junctions within the search range.
01:23
It will also recalculate the available flow at the hydrant until none
01:27
of the pressures drop below the minimum pressure constraint or 20 psi.
01:31
In this example,
01:33
it is important to understand that any junctions within
01:36
your search range with a standard simulation pressure,
01:38
less than the minimum pressure constraint will not be in the results.
01:44
This is because pressure is reduced as the flow is increased.
01:48
A standard simulation would be lower flows than firef
01:50
flow where demands are increased by 1000 plus GPM.
01:55
Therefore,
01:56
if a junction's pressure is less than
01:57
the constraint before large demands are applied,
01:60
adding that increased flow is only going to further reduce pressure.
02:04
So essentially if a junction cannot maintain the
02:06
minimum pressure constraint before firef flows are applied,
02:09
then there is no way it could handle those intended firef flows.
02:13
Click run
02:15
the Firefly design report opens automatically in the report manager.
02:19
If you are prompted to switch to the most recent output data, click yes.
02:25
Review the report.
02:27
The column headers show you the resulting hydrant and critical node data
02:32
for this analysis.
02:33
Review the critical node pressure at fire demand field to
02:36
see if the entire system can support the firef flows.
02:39
This field is identifying the lowest pressure in the
02:42
search range when the firef flow demand is applied,
02:44
which is the most constraining pressure in the search range
02:48
if this is greater than or equal to your pressure constraint.
02:51
In this case, 20 psi for these units,
02:53
then the entire system can support what is required
02:57
when you are finished. Close the report manager.
Video transcript
00:04
A design firef flow simulation allows you to add a secondary pressure constraint
00:08
to identify the junction with the lowest pressure within a search range.
00:12
The hydrant available flow calculated in the standard firef
00:15
flow simulation is recalculated based on this critical node.
00:19
So its pressure does not drop below the minimum pressure constraint.
00:22
This new value is called the hydrant design flow
00:26
to begin. Double click the desired project dot APR X file to open
00:30
Agis Pro.
00:32
Once the project starts,
00:33
click the info water pro tab to open the info water pro ribbon
00:38
in the project panel, click initialize
00:42
on the info water pro ribbon in the analysis panel, click run
00:47
in the run manager on the firef flow tab.
00:49
Enable run firef flow on domain only to
00:52
restrict the analysis to the selected domain.
00:57
Also enable design firef flow to add the pressure constraint
01:00
but keep the minimum pressure accuracy and minimum iteration values as they are
01:06
also keep in mind that the minimum pressure is set to 20 psi
01:10
lastly expand the critical node, search range dropdown and select domain nodes.
01:17
Now while simulating a hydrant flowing,
01:19
the software will check the pressures at all junctions within the search range.
01:23
It will also recalculate the available flow at the hydrant until none
01:27
of the pressures drop below the minimum pressure constraint or 20 psi.
01:31
In this example,
01:33
it is important to understand that any junctions within
01:36
your search range with a standard simulation pressure,
01:38
less than the minimum pressure constraint will not be in the results.
01:44
This is because pressure is reduced as the flow is increased.
01:48
A standard simulation would be lower flows than firef
01:50
flow where demands are increased by 1000 plus GPM.
01:55
Therefore,
01:56
if a junction's pressure is less than
01:57
the constraint before large demands are applied,
01:60
adding that increased flow is only going to further reduce pressure.
02:04
So essentially if a junction cannot maintain the
02:06
minimum pressure constraint before firef flows are applied,
02:09
then there is no way it could handle those intended firef flows.
02:13
Click run
02:15
the Firefly design report opens automatically in the report manager.
02:19
If you are prompted to switch to the most recent output data, click yes.
02:25
Review the report.
02:27
The column headers show you the resulting hydrant and critical node data
02:32
for this analysis.
02:33
Review the critical node pressure at fire demand field to
02:36
see if the entire system can support the firef flows.
02:39
This field is identifying the lowest pressure in the
02:42
search range when the firef flow demand is applied,
02:44
which is the most constraining pressure in the search range
02:48
if this is greater than or equal to your pressure constraint.
02:51
In this case, 20 psi for these units,
02:53
then the entire system can support what is required
02:57
when you are finished. Close the report manager.
A Design Fireflow simulation allows you to add a secondary pressure constraint to identify the junction with the lowest pressure within a search range. The hydrant available flow calculated in the standard fireflow simulation is recalculated based on this critical node, so its pressure does not drop below the minimum pressure constraint. This new value is called the hydrant design flow.
To restrict the analysis to the selected domain and configure the Design Fireflow simulation:
While simulating a hydrant flowing, the software will check the pressures at all junctions within the search range. It will also recalculate the available flow at the hydrant until none of the pressures drop below the minimum pressure constraint (20 psi in this example).
The Fireflow Design report opens automatically in the Report Manager.
IMPORTANT: Any junctions within your search range with a standard simulation pressure less than the minimum pressure constraint will not be in the results. This is because pressure is reduced as the flow is increased. A standard simulation would be lower flows than fireflow, where demands are increased by 1000+ gpm. Therefore, if a junction's pressure is less than the constraint before large demands are applied, adding that increased flow is only going to further reduce pressure. So essentially, if a junction cannot maintain the minimum pressure constraint before fireflows are applied, then there is no way it could handle those intended fireflows.
The column headers show the resulting hydrant and critical node data. The Critical Node Pressure at Fire Demand field is identifying the lowest pressure in the search range when the fireflow demand is applied, which is the most constraining pressure in the search range. If this is greater than or equal to your pressure constraint—in this case, 20 psi for these units—then the entire system can support what is required.
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