Altura
The head H is defined as
For the determination of the intersection of system curve and pump curve it is useful to relate the static pressure of the pumps outlet p´3 to the axis of it´s suction side. Static pump pressure p3 corresponds to the static pressure of the system curve. Pressure difference (p3-p2) can be calculated without knowledge of the difference in height Δhp of the pumps suction- und pressure side.
| H | : | Altura |
| Δhp | : | Difference in height of the pumps suction- and pressure side. |
| p2 | : | Static pressure on pumps suction side. |
| p´3 | : | Static pressure on pumps pressure side. |
| p3 | : | Static pressure on pumps pressure side calculated back to level of pump shaft (axis of suction flange) |
| v2, d2 | : | Average speed on suction sided with inner diameter d2 |
| v3, d3 | : | Average speed on pressure side with inner diameter d3 |
| ρ | : | Densidad |
| g | : | Aceleración de la gravedad, g = 9,81 m/s2 |