• ID: Unique identifier assigned to this element.
• Label: Descriptive label for this element.
• Notes: Additional information about this element.
• GIS-IDs: List of associated IDs on the GIS/data-source side.
• Hyperlinks: Associate one or more web link, photo, word processing document, or other file with this element.
• Discharge Coefficient (Transient): Discharge coefficient, Cv, is defined as: Flow / (Pressure Drop) ^ 0.5.
• Operating Rule: Specifies the operation of the valve during a transient simulation.
• Hydraulic Grade Setting (Initial, Transient): The initial HGL setting for the transient simulation.
• Valve Characteristics: Specifies the valve characteristics definition to be used for this valve. If the Valve Characteristic Curve is not defined then a default curve will be used. The default curve will have (Relative Closure, Relative Area) points of (0,1) and (1,0).
• Valve Type: Choices: Butterfly, Needle, Circular Gate, Globe, Ball, User Defined
• Setting Type: Choices: Pressure, Hydraulic Grade
• Pressure Setting (Initial): Specify the initial pressure setting for the valve.
• Hydraulic Grade Setting (Initial): Specify the initial hydraulic grade setting for the valve.
• Pattern (Valve Settings): Allows you to apply a pattern to make changes to the valve's setting over time for use in extended period simulations. For settings patterns to work the valve must have a Status (Initial) equal to Active. For pressure valves the setting applies to the valve's effective pressure setting irrespective of the Setting Type. Note that changes made to a valve's setting by patterns will override any settings changes made by controls.
• Status (Initial): Choices: Active, Inactive, Closed
• Diameter (Valve): Inside diameter of the valve. Used to calculate the velocity through the valve and a corresponding minor loss when a minor loss coefficient is entered.
• Valve Coefficient Type: Specifies which type of coefficient to enter for the control valve. If entering discharge coefficient, the value is internally converted into an equivalent headloss coefficient (minor loss).
• Discharge Coefficient (Fully Open): The discharge coefficient of the valve when fully open. Used in lieu of minor loss for valves of this coefficient type.
• Specify Local Minor Loss?: If True, the minor coefficient for the element is manually set in the Minor Loss Coefficient (Local) field; otherwise the value is derived from the minor loss library.
• Minor Loss Coefficient (Local): User-input minor loss coefficient. You can either type the value directly in this field or select the value from the minor loss library. The minor loss is applied to the valve when it is fully open (inactive). Note that minor losses do not apply to the following valve types: General Purpose Valve and Valve With Linear Area Change. These two valve types do not support a (fully) open status and always apply the head/flow relationship defined by their headloss curve and discharge coefficient, respectively.
• Valve Type: Specify the type of valve. Choices are Butterfly, Needle, Circular Gate, Globe, Ball, and User Defined.
• Modulate Valve During Transient?: If True, the valve closure will be automatically adjusted to maintain constant valve outlet pressure.
• Opening Rate Coefficient: A constant that relates PRV opening rate during a transient simulation to the difference between the PRV pressure setting and the computed PRV outlet pressure. Units are change in the valve relative closure per second per unit of pressure difference.
• Closing Rate Coefficient: A constant that relates PRV closure rate during a transient simulation to the difference between the PRV pressure setting and the computed PRV outlet pressure. Units are change in the valve relative closure per second per unit of pressure difference.
• Operating Rule: Specifies the operation of the valve during a transient simulation.
• Status (Initial, Transient): Choices: Active, Inactive, Closed
• Elevation: Elevation at centroid of junctions, valves, and pumps; the ground elevation at tanks; the hydraulic grade at reservoirs.
• Concentration (Initial): Specify the initial concentration for the global concentration at the selected element.
• Age (Initial): Specify the initial age of the fluid at the selected element.
• Installation Year: Specify the install year of the element. It does not affect the calculations.
• Trace (Initial): Specify the initial trace amount at the current location.
• Zone: Specify the zone for the element.
• Hydraulic Grade Setting (Calculated): Hydraulic Grade Setting during current time step.
• Pressure Setting (Calculated): Pressure setting for valve at current time step.
• Flow: Total flow through the valve.
• Velocity: Velocity of flow traveling through the valve.
• Headloss: Change in head across the valve.
• Pressure Loss: Change in pressure across the valve.
• Hydraulic Grade (From): Calculated hydraulic grade at the entrance of the valve.
• Hydraulic Grade (To): Calculated hydraulic grade at the exit of the valve.
• Pressure (From): Calculated pressure at the entrance of the valve.
• Pressure (To): Calculated pressure at the exit to the valve.
• Flow (Absolute): Magnitude of flow through the selected valve.
• Status (Calculated): Choices: Active, Inactive, Closed
• Minor Loss Coefficient (Unified): Displays the current minor loss value for the element, depending on whether its derived or local.
• Age (Calculated): Age at selected element for current time step.
• Trace (Calculated): Trace at selected element for current time step.
• Concentration (Calculated): Concentration at selected element for current time step.
• Has Calculation Messages Now?: If true then the current element has associated calculation warning messages for the current time step.
• Is Closed?: True if the current element is closed during the current time step.
• Is Open?: Set to true if open during the current time step.
• Is Initially Closed?: If true, the initial condition for the control element is "Closed" or "Off."
• Controlled?: Is true if a control action in the current control set references the selected element.
• Cannot Deliver Flow or Head?: If true then the cannot deliver head or cannot deliver flow warning was generated for the element for the current time step.
• Head (Maximum, Transient): Maximum head at node over the course of the transient simulation.
• Head (Minimum, Transient): Minimum head at node over the course of the transient simulation.
• Pressure (Maximum, Transient): Maximum pressure at node over the course of the transient simulation.
• Pressure (Minimum, Transient): Minimum pressure at node over the course of the transient simulation.
• Air Volume (Maximum, Transient): Maximum air volume at node over the course of the transient simulation. Not applicable to Reservoirs and Rating curves.
• Vapor Volume (Maximum, Transient): Maximum vapor volume at node over the course of the transient simulation. Not applicable to Reservoirs and Rating curves.

Pressure Sustaining Valve (PSV) Attributes

• ID: Unique identifier assigned to this element.
• Label: Descriptive label for this element.
• Notes: Additional information about this element.
• GIS-IDs: List of associated IDs on the GIS/data-source side.
• Hyperlinks: Associate one or more web link, photo, word processing document, or other file with this element.
• Discharge Coefficient (Transient): Discharge coefficient, Cv, is defined as: Flow / (Pressure Drop) ^ 0.5.
• Operating Rule: Specifies the operation of the valve during a transient simulation.
• Hydraulic Grade Setting (Initial, Transient): The initial HGL setting for the transient simulation.
• Valve Characteristics: Specifies the valve characteristics definition to be used for this valve. If the Valve Characteristic Curve is not defined then a default curve will be used. The default curve will have (Relative Closure, Relative Area) points of (0,1) and (1,0).
• Valve Type: Choices: Butterfly, Needle, Circular Gate, Globe, Ball, User Defined
• Setting Type: Choices: Pressure, Hydraulic Grade
• Pressure Setting (Initial): Specify the initial pressure setting for the valve.
• Hydraulic Grade Setting (Initial): Specify the initial hydraulic grade setting for the valve.
• Pattern (Valve Settings): Allows you to apply a pattern for changes to the valve's setting over time for extended period simulations. (Note that patterns override settings changes made by controls).
• Status (Initial): Choices: Active, Inactive, Closed
• Diameter (Valve): Inside diameter of the valve. Used to calculate the velocity through the valve and a corresponding minor loss when a minor loss coefficient is entered.
• Valve Coefficient Type: Specifies which type of coefficient to enter for the control valve. If entering discharge coefficient, the value is internally converted into an equivalent headloss coefficient (minor loss).
• Discharge Coefficient (Fully Open): The discharge coefficient of the valve when fully open. Used in lieu of minor loss for valves of this coefficient type.
• Specify Local Minor Loss?: If True, the minor coefficient for the element is manually set in the Minor Loss Coefficient (Local) field; otherwise the value is derived from the minor loss library.
• Minor Loss Coefficient (Local): User-input minor loss coefficient. You can either type the value directly in this field or select the value from the minor loss library. The minor loss is applied to the valve when it is fully open (inactive). Note that minor losses do not apply to the following valve types: General Purpose Valve and Valve With Linear Area Change. These two valve types do not support a (fully) open status and always apply the head/flow relationship defined by their headloss curve and discharge coefficient, respectively.
• Status (Initial, Transient): Choices: Active, Inactive, Closed
• Elevation: Elevation at centroid of junctions, valves, and pumps; the ground elevation at tanks; the hydraulic grade at reservoirs.
• Concentration (Initial): Specify the initial concentration for the global concentration at the selected element.
• Age (Initial): Specify the initial age of the fluid at the selected element.
• Installation Year: Specify the install year of the element. It does not affect the calculations.
• Trace (Initial): Specify the initial trace amount at the current location.
• Zone: Specify the zone for the element.
• Hydraulic Grade Setting (Calculated): Hydraulic Grade Setting during current time step.
• Pressure Setting (Calculated): Pressure setting for valve at current time step.
• Flow: Total flow through the valve.
• Velocity: Velocity of flow traveling through the valve.
• Headloss: Change in head across the valve.
• Pressure Loss: Change in pressure across the valve.
• Hydraulic Grade (From): Calculated hydraulic grade at the entrance of the valve.
• Hydraulic Grade (To): Calculated hydraulic grade at the exit of the valve.
• Pressure (From): Calculated pressure at the entrance of the valve.
• Pressure (To): Calculated pressure at the exit to the valve.
• Flow (Absolute): Magnitude of flow through the selected valve.
• Status (Calculated): Choices: Active, Inactive, Closed
• Minor Loss Coefficient (Unified): Displays the current minor loss value for the element, depending on whether its derived or local.
• Age (Calculated): Age at selected element for current time step.
• Trace (Calculated): Trace at selected element for current time step.
• Concentration (Calculated): Concentration at selected element for current time step.
• Has Calculation Messages Now?: If true then the current element has associated calculation warning messages for the current time step.
• Is Closed?: True if the current element is closed during the current time step.
• Is Open?: Set to true if open during the current time step.
• Is Initially Closed?: If true, the initial condition for the control element is "Closed" or "Off."
• Controlled?: Is true if a control action in the current control set references the selected element.
• Cannot Deliver Flow or Head?: If true then the cannot deliver head or cannot deliver flow warning was generated for the element for the current time step.
• Head (Maximum, Transient): Maximum head at node over the course of the transient simulation.
• Head (Minimum, Transient): Minimum head at node over the course of the transient simulation.
• Pressure (Maximum, Transient): Maximum pressure at node over the course of the transient simulation.
• Pressure (Minimum, Transient): Minimum pressure at node over the course of the transient simulation.
• Air Volume (Maximum, Transient): Maximum air volume at node over the course of the transient simulation. Not applicable to Reservoirs and Rating curves.
• Vapor Volume (Maximum, Transient): Maximum vapor volume at node over the course of the transient simulation. Not applicable to Reservoirs and Rating curves.