Butterfly Valve: Oper. Conds Tab

Variable Definitions, Ranges and Default Values

The following table shows a brief description of the variables appearing in this tab. The table also displays their default values and their generally acceptable range:

Variable	Default Value	Range

● Volumetric Throughput Per Valve (L/h) The volumetric flowrate of the feed stream per valve.	0.0	Positive
○ Pressure Drop (Pa) The pressure drop in the valve.	100.0	Positive
○ Percentage open (%) The percentage that the valve is open.	100	(0,100]
○ Setup Time (min) The amount of time (per cycle) spent before each operation is carried in preparation for the actual execution of the operation. It may involve actions like cleaning, vacuuming, setting up of equipment, etc. which the user opted not to model explicitly.	0.0	Positive
◙ Process Time (min) The actual duration of the operation (per cycle).	240.0	Positive
○ Ignore Labor? Check this box to ignore labor for this operation. This option is used only if the process time is set by a master-slave relationship.	Yes	Yes/No

Symbol Key: ○ User-specified value (always input); ● Calculated value (always output); ◙ Sometimes input, sometimes output

Specification Choices / Comments

The following list describes the available specification choices in this tab; for more details on how these are implemented, see Liquid Pressure Drop in a Globe Valve: Modeling Calculations.

•Pressure Change...

The user specifies the % opening of the control valve. A “linear flow characteristic” valve type is assumed. In Rating Mode, the pressure change is calculated. In Design Mode, it is always specified.