Modelling hydrant flows

You can switch on Hydrant Mode at a Basic Node or Hydrant Node to model hydrant discharge flows as part of a fire flow or mains flushing analysis. A time-varying Hydrant Opening profile for the node is set using a series of date-time / flow value pairs. The feature uses pressure dependant theory to calculate the relevant flow discharge.

To model hydrant flow:

  1. open the property sheet for the appropriate node and choose the Hydrant Flow Profile Page. If the Hydrant Flow Profile Page is not visible, click the Add Control button to add control parameters for the node.
  2. enter the time varying profile for the hydrant using the Hydrant Flow grid. Enter a series of dates and times in the Date Time column, and for each time set the percentage opening in the Opening column.
  3. check the Linear Profile box for linear interpolation to be used between data points. If this box is unchecked each percentage opening value entered is maintained until the next date / time entry, or until the end of the simulation.
  4. select an option for extending the profile before the first time defined in the grid:
  5. select an option for extending the profile after the last time defined in the grid:
  6. check the Repeat Profiles box to repeat the first 24 hours of the defined profile for the duration of the simulation
  7. decide whether local demand is to be applied to the node during simulation by setting the Keep Local Demand checkbox on the Node Control Page of the property sheet. The two options are:

Nodes

Exceptional Demand

Hydrant Flow Profile Page