Create a New Deterministic Simulation

In HEC-WAT, a simulation is created by combining an analysis period and an alternative to compute results across the models in the program order for a given time window. Once model alternatives have been imported and HEC-WAT alternatives and analysis periods have been defined, the user can create a simulation.  

Note

At least one unused analysis period for the selected alternative must exist before a simulation can be created. 

A new deterministic simulation can be created from the Study Tree or from the Alternative Simulation Manager. To create a new simulation from the Study Tree, right-click on the Simulation node in the Study Tree, and click New from the shortcut menu; or, from the Study Pane toolbar, click . Alternatively, from the Alternative and Simulation Manager (opened from the WAT Tools toolbar by clicking ), from the table select an empty cell, right-click and select Create Simulation from the shortcut menu. Either way the Create New Simulation dialog box opens. 

The Create New Simulation dialog box provides the ability to create a new simulation.

1. Define a required name in the Name box. Optionally, add a description in the Description box.
2. Do NOT select the Run FRA checkbox. This checkbox is used to denote a Flood Risk Analysis simulation, and should be left unchecked for a deterministic simulation.
3. Select the HEC-WAT alternative for the simulation from the Alternative list.

4. Select the analysis period that represents the window for the desired time window from the Analysis Period list.

   

   Auto Generated DSS F-Part name

   Once an analysis period is selected, HEC-WAT builds a default DSS F-Part based on the alternative and analysis period selected.

5. Select the appropriate program order from the Program Order list.

   

   Creating a New Program Order

   The user can also create a new program order by clicking New. The New Program Order dialog box will open; follow the instructions in Program Order for creating a program order.

6. The software applications appear in the order they were selected in the chosen program order in the Programs table. Select the appropriate model alternative (i.e., plan, run) for each program. From the Alternative column, for example, from the list for HMS, select the appropriate HEC-HMS run ((RUN)Feb_1986). Repeat the process for the other software applications.

   

   Simulation Time Window

   Connecting a model alternative to a time window modifier alternative in the Models table modifies the simulation time window for that model alternative, either by shortening or expanding it. As a best practice, subsequent model alternatives in the simulation should generally be connected to the same time window modifier alternative to ensure that those model alternatives' simulation time windows match that of prior model alternatives. If the simulation time windows of the subsequent model alternatives are not modified, there is a risk that those model alternatives' time windows will be larger than the previous model alternative. This could mean that adequate input data might be unavailable for those model alternatives and the simulation will not complete. For more information regarding the Simulation Time Window time window modifier alternative, please review the Time Window Modifier Plugin document.

7. To use the Time Window Adjustment option for a model alternative, please review the Time Window Adjustments section.
8. After all of the model alternatives have been selected, click OK to close the Create New Simulation dialog box.
9. From the HEC-WAT main window, the created simulation appears on the Study Tree, under the Simulations folder.

10. The next step is to have the model alternatives within a simulation communicate with each other by linking model alternatives. To link the model inputs and outputs, from the Study Tree, right-click the simulation to open the simulation shortcut menu, and select the Model Linking Editor option to open the Model Linking Editor. 

11.