EPANET - Tank

Tanks are nodes with storage capacity, where the volume of water stored can vary over time during a simulation.

Tanks must operate within their minimum and maximum levels. EPANET stops flow if a tank is at its minimum level. It stops any Inflow if the tank is at its maximum level, unless its Can Overflow property is set to YES. In that case, any input becomes overflow (i.e., spillage).

Tanks can also serve as water quality source points.

In addition to the shared properties of EPANET Nodes, tanks also have the following properties:

• Volume
  • Volume Curve - Volume curve used to describe the relationship between tank volume and water level A volume curve determines how the storage tank volume (Y) varies as a function of water level (X)
  • Diameter - The diameter of the tank.
    For cylindrical tanks, this is the actual diameter.
    For square or rectangular tanks, it may have an equivalent diameter equal to 1.128 times the square root of the cross-sectional area.
    For tanks whose geometry will be described by a curve (see above), it can be set to any value.
    This is a required property.
  • Can Overflow - if set to YES, any inflow to a full tank becomes overflow (ie spillage).
    Otherwise any links that would normally send flow to the tank are temporarily closed when the tank is full
  • Minimum Volume - The volume of water in the tank when it is at its minimum level
• Epanet
  • Elevation - The elevation above a common tank bottom datum.
• Mixture Model
  • Mixing Fraction - Fraction of the total tank volume comprising the inlet-outlet compartment of the two-compartment mixing model (2COMP)
  • Mixing Model - Type of water quality mixing that occurs inside the tank
• Levels
  • Starting Level - The height of the water surface above the bottom elevation of the tank at the start of the simulation
  • Maximum Level - The maximum height of the water surface above the lower elevation that will be maintained
  • Minimum Level - The minimum height of the water surface above the lower elevation that will be maintained
• Reactions
  • Reaction Coefficient - The mass reaction coefficient for chemical reactions in the tank. Use a positive value for growth reactions and a negative value for decay
• Calculations - are filled in by the command EPANETCALC, when it succeeds in the simulation
  • Flow Balance - Flow Balance
  • Water Level - Calculated water level for the reservoir

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  To view the tank properties, click the icon in the Properties Tab or in the command SPROPS: