Two identical pumps added in parallel double flow at fixed head; added in series double head at fixed flow (against a flat enough system curve).
Formula
$$ Q_\text{parallel} = n \cdot Q_1, \quad H_\text{series} = n \cdot H_1 $$
Symbol legend
| Symbol | Meaning | Unit | Source |
|---|---|---|---|
| $Q_1$, $H_1$ | Single-pump duty-point values | m³/h, m | pump curve |
| $n$ | Number of pumps | - | plant design |
Sources
- Hydraulic Institute - Centrifugal pumps.