The Control Specifications command allows the user to define when the HEC-HMS hydrology simulation starts and stops, and what computational time interval is to be used in the simulation. Each control specification establishes a time window over which a simulation will be performed. The window is specified using a separate start date, start time, end date, and end time. There is no limit on the length of a time window or the number of simulation time steps it can contain. The time interval defined in the control specification will also be used in displaying time-series results from the simulation.
Follow the steps below to use the Control Specifications command:
- From the Analysis ribbon menu, select the Control Specifications command.
- The Control Specifications dialog box will be displayed.
The following sections describe how to define the control specifications and interact with the above dialog box.
Select Control Specifications
The Select Control Specifications section is used to define the HEC-HMS control specifications ID. This allows multiple control specifications to be defined for different conditions. The section can be used to create a new control specification, copy existing control specifications data to a new control specification, as well as delete a control specification. In addition, the user can navigate between previously defined control specifications and enter a description detailing the current control specification.
Simulation Time Window
The Simulation Time Window section defines the starting date and time and ending date and time of the HEC-HMS hydrology simulation. The user can click on the [Date] button, which displays a calendar date selector from which the user can select a specific date. Similarly, the user can click on the [Time] button, at which point the software displays a 24-hour time selector from which the user can select a specific time.
Simulation Time Setting
The Simulation Time Setting section defines the computational time step to be used in the HEC-HMS hydrology simulation.