At the moment, there is no dedicated tool or attribute that directly provides the internal volume of a pipe.
However, a pseudo‑attribute can be used to approximate it: BRWWEI.
This pseudo‑attribute returns the wet weight of the pipe (or branch or individual component, depending on the current CE), meaning the weight including the fluid. The calculation relies on the following principles:
1. Fluid reference
The FLUREF attribute must be defined at both PIPE and BRAN levels. It must point to a FLUI element in the Property Database.
2. Internal diameter consideration
The calculation uses the internal diameter of the pipe. Wall thickness must therefore be correctly managed in Paragon, via the Pipe Data Tables (PDATAB) and the associated Wall Thickness Tables (WTHTAB).
3. Internal volume estimation
The internal volume is derived from simple geometric primitives based on the connection P‑Points:
- circular tori for elbows and bends,
- truncated cones for reducers,
- cylinders for all other components.
The expression BRWWEI – BRWEI gives the weight of the fluid alone (Wet Weight – Dry Weight).
4. Converting fluid weight to volume
The internal volume is obtained by dividing the fluid weight by its density. The density is defined in the SDEN or TDEN attribute of the FLUI element in the Property Database.
Note: The resulting volume is an approximation.
For example:
Q ( BRWWEI – BRWEI ) / ( DENSITY OF 1 OF 1 OF FLUREF )
