Method
Nominal hydro-pneumatic tank volume from required drawdown and supplied acceptance factor.
Equations
Vt = VdAF
Symbols and units
| Symbol | Quantity | Unit |
|---|---|---|
| Inputs | ||
| Vd | Required drawdown | L |
| AF | Acceptance factor | 0–1 |
| Results | ||
| Vt | Required nominal tank volume | L |
Assumptions and limits
- Acceptance factor is a required reference input; it is not derived from pressure settings.
In practice
- The acceptance factor depends on the pre-charge and the pump cut-in and cut-out pressures; take it from the tank maker’s data.
Worked example
The input values are the calculator's own verification test, run through the calculator. They show the working; they are not design values.
Inputs
| Vd | Required drawdown | 100 L |
| AF | Acceptance factor | 0.5 0–1 |
Results
| Vt | Required nominal tank volume | 200 L |
A preliminary check for engineer review, not an engineering approval. The project calculation to the applicable codes, authority requirements and specification governs.