Understanding scenarios, datasets, and facilities

Step-by-step:

Scenario Management allows a hydraulic modeler to analyze and compare multiple alternatives based on different features, such as demands, pump controls, or tank sizes. Before creating scenarios, it is helpful to understand how they work, and the relationship scenarios have with facilities and datasets. Scenarios are created and modified using the Scenario Explorer.

To open the Scenario Explorer:

  1. In the Model Explorer, Scenario toolbar, click Scenario Explorer.
  2. OR, the Current Scenario is displayed in the toolbar. Expand the drop-down to change scenarios.
  3. OR, in the Model Explorer, Command Center tab, expand the Scenario folder to access the Scenario Explorer, Dataset Manager, Edit Active Scenario, and Compare Data Scenario.
    The Model Explorer, Command Center tab displaying the available scenario tools

Datasets are the key component of scenarios, and are used to represent any differences, such as pipe diameter, tank size, or pump curve.

To select datasets for a scenario:

  1. Open the Scenario Explorer (see step 1).
  2. Click the Data Set tab.
    The Scenario Explorer with the Data Set tab open

To view, clone, and create new datasets, use the Dataset Manager.

The Dataset Manager

Datasets are modified by editing attributes and parameters. The dataset you choose to edit depends on the element and property being studied. Many single elements (for example, one junction) can have a BASE dataset and a non-BASE dataset, such as a Demand Set and a Fireflow Set. Most scenarios contain many BASE datasets, which is why editing BASE datasets from the BASE scenario is recommended. A common mistake is editing one non-BASE dataset, then another feature attribute that references a BASE dataset. You should understand exactly which parameters are contained in each dataset.

All scenarios originate from the BASE scenario, or parent scenario. Child scenarios are created when scenarios are created new or cloned. Child scenarios can then either inherit the dataset from the parent scenario, or they can use a scenario-specific dataset. An inherited dataset will update automatically in the child scenario to match if the parent scenario is changed. But a scenario-specific dataset will not change if the parent scenario is changed. Child scenarios do not inherit the facility definition, which always reverts to the active network.

A presentation slide illustrating the scenario inheritance rule

To edit the datasets of the active scenario, in the Scenario Explorer, click Edit Active Scenario.

Be aware that the BASE scenario cannot be edited using this tool. The primary purpose of this tool is to allow you to create a new dataset in a scenario to replace a dataset without needing to change scenarios.

A scenario may simulate a unique portion of the system or the entire network. For example, any proposed pipes should not be included in a scenario that represents existing conditions.

To manage which network elements apply to a scenario, in the Scenario Explorer, click the Facility tab.

The Scenario Explorer, with the Facility tab open

  • Active Network - The active facilities when the scenario is selected will remain active. No change is made when switching to the scenario.
  • Entire Network - The entire network becomes active when switching to the scenario. This option is best used for an ultimate build-out model with no build-out alternates.
  • Query Set - The elements that match the query are activated when switching to the scenario. All elements not matching the query are deactivated. This selection dynamically includes newly created facilities when the attributes match the query statement.
  • Intelli-Selection – InfoWater Pro remembers what was active and inactive when a scenario was last used and reactivates the same features. This is best used for scenarios that will not require facility changes in the future. You can also use the Facility panel in the InfoWater Pro ribbon to manage your facilities. The tools in this panel work similarly to the Domain tools.
  • Inherited – The scenario uses the facilities set in the parent scenario.

To set specific simulation and report options as well as time settings, in the Scenario Explorer, click the General tab. If these parameters are not specified in the Scenario Explorer, then the options and settings that were last selected will be displayed when the Run Manager is opened.

The Scenario Explorer, with the General tab open

IMPORTANT: When setting up a scenario, switch to all the tabs in the Scenario Explorer to make sure that everything is set up how you want.

In the Scenario Explorer, you can create a Batch Run to run simulations of multiple scenarios.

The Batch Simulation Manager, with multiple simulations highlighted for a batch run

The results of all scenarios simulated in a batch can be compared in reports and graphs. You can also compare the scenarios themselves to see the differences between them.