EPANET - Time Patterns

A time standard is a collection of multipliers that can be applied to a quantity to allow it to vary over time. Water demands, volumes of reservoir, schedules of pumps and water quality source inputs may have standards of time associated with them.

The time interval used in all patterns is defined with the project's time options. Within that range, an amount remains at a constant level, equal to the product of its face value and the pattern multiplier for that range. Although all time patterns must use the same time frame, each one can have a different number of periods. When the simulation clock exceeds the number of periods in a pattern, the pattern reverts to the first period again.

In general, time patterns have the following properties:

• Identification
  • Description - Use a friendly description when the item name is not enough
  • Name - Name of the item
    avoid very long names
  • Priority - Information about the current state of the item. It might be:
    • Neutral: no problem
    • Critical: Some issue that prevents the item from being calculated or used
• Epanet
  • Pattern Time Range - Time range used with all time patterns. Normal default is 1 hour

EPANET uses the following time standards:

• Pump Pattern - controls pump operation
• Demand Pattern - characterizes the variation in demand over time for the main consumer category at the junction
• Head Pattern - models time variation in total reservoir load
• Price Pattern - represent changes in the price of energy
• Quality Default - makes font quality vary over time

Note: To create/edit a Time Pattern, use the command EPANETPATTERNS