This dialog view lets you set up a hydrant testing simulation to test a selection of nodes in turn against a number of fire flow test parameters. A
hydrant testing report is produced containing details of flows and pressures at each test node and whether the node passed or failed. A node will pass if the minimum fire flow required can be supplied without breaching any of the pressure constraints applied.
Hydrant testing will be performed only on selected regular nodes and hydrant nodes.
The
fire flow data object is used to specify fire flow test parameters for regular nodes. Fire flow test parameters for hydrant nodes may be specified at individual hydrant nodes or provided from the fire flow data object.
The hydrant testing simulation is performed as a series of steady state analyses. Each node is considered independently, as if no other hydrant in the system is open.
If a test duration time is specified, the hydrant test is run from the test time and results are evaluated from the delay time (if set) until the end of the combined test-time, delay time, and duration. All the hydrant tests are performed with a fully open hydrant.
Note: The hydrant testing can only use fully open hydrants for non-zero duration as it's not possible to do availability tests at every time-step and produce compatible results for the grid display; there will be completely different values for the available flow and mrp at every time-step during the test.
This dialog view is opened by selecting
Hydrant Testing on the Fire Flow Options dialog.
| Parameter
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Description
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Include Nodes
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| Selection List
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You must add a
selection list of nodes to be tested. Only regular and hydrant type nodes will be tested. Other objects in the selection will be ignored.
For regular Hydrant Testing, the selection list is mandatory. However, if using GMR Hydrant Testing, the selection list should be removed for reasons of efficiency. When the selection list is not removed, the application will report a warning message asking you to remove it. The selection list is replaced by the Analysis Tab on the
GMR Configuation Object.
When a Fire Flow run is validated and saved with a selection list, an error message will be displayed.
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Fire Flow Data
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| Fire Flow
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Select the
fire flow data object to be used during analysis.
The data in the fire flow data object will be applied at all regular test nodes.
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| At Hydrant Nodes
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There are two options for the use of the fire flow data object:
- Provides missing values for Hydrant Testing Constraints - Data from the fire flow data object item will be used for fire flow constraints data fields that have no values defined at the hydrant node to be tested.
- Overrides values defined at the Hydrant
- Data from the fire flow data object will override values defined at the hydrant node to be tested.
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Fire Demand Data
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| Hydrant Testing Time
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This must be between simulation start and end time.
Setting the time here sets the same value on the Forced Fire Flow view.
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| Cancel Non-Hydrant Flow at Test Nodes
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Check this box to cancel any local demand and exceptional flow applied to the test node at hydrant testing time (see above).
Note: Checking this box will override the
Keep Local Demand check box in the
fire flow data object.
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| Test Results Delay
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You can use this to set a delay between the start of the test and the point from which results will be calculated.
This will allow the operating hydrant to fully interact with the rest of the network while running up to the results time, so that control valves, PSTs, etc. can react to changing conditions, including any changes in reservoir levels.
Setting the delay time here sets the same value on the Forced Fire Flow view.
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| Set Test Duration
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You can set a test duration time by checking the box and then entering a number of minutes into the accompanying input box.
If a test duration time is specified, the hydrant test is run from the test time and results are evaluated from the delay time (if set) until the end of the combined test-time, delay time, and duration. All the hydrant tests are performed with a fully open hydrant.
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| Options
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Use Zone Constraints
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Check this box to enforce zone constraints during analysis.
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Use Network Constraints
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Check this box to enforce network constraints during analysis.
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Apply constraints to demand nodes only
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Check this box to enforce zone constraints and network constraints at nodes with assigned demand only.
If this box is unchecked, all basic nodes will be tested against constraints. Reservoir, Well and Fixed Head nodes will be excluded from the check.
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| Use maximum velocity
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Hydrant Testing and Forced Fire Flow can operate with maximum velocity as a constraint. This is a check box in the options for the simulation to enable this constraint.
- There is a global maximum for this constraining velocity, in the options dialog.
- Also, each link’s control allows a setting of maximum velocity. This individual setting will be used if the options check box is set, and the individual setting overrides the global maximum for that link.
The hydrant report shows, for each hydrant tested, the name of a “maximum velocity link”, and that link’s maximum velocity and its constraint velocity.
- If no links experience a velocity constraint, then the link with the greatest velocity is displayed. Also, if that link has its own defined constraint, then that link’s particular constraint is displayed. Otherwise the global constraint from the simulation options is displayed.
If one or more links experience a constraint on their velocity, then one of those links is displayed along with its corresponding maximum velocity and constraint velocity. (The constraint should be viewed as a ceiling velocity which is approached but not exceeded. The link that is displayed is the one that most nearly approaches its constraint.)
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Calculate Pressure at Min and Max Fire Flow
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Check this box to calculate pressures at the minimum and maximum fire flow.
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Calculate Open Hydrant Flow
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Check this box to calculate the maximum flow at the hydrant when the hydrant is fully open.
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Calculate Hydrant Curves
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Check this box to calculate a hydrant curve of Residual Pressure against flow.
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| Test Flows (grid)
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Available only if the
Calculate Hydrant Curves box is checked.
You can enter up to twenty flows in the grid.
Not available if the
Set Test Duration box is checked.
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| Test cases per thread (parallel processing)
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You can use this to distribute the test cases when using parallel processing.
For GMR fire flow hydrant tests, by setting a value of 0, an algorithm is used to calculate a suitable value to be used.
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