Recommendations
Septic tank project - SALUTAR dimensionsCircular weirAtmospheric pressure given altitudeAir specific massDynamic viscosity of atmospheric airEstimation of the required NPSH, using the Thoma factor

Available NPSH calculation

Input data

Temperature

Flow

Diameter (Ds)

Diameter (Db)

Length (L1)

Length (L2)

Level (EL.s)

Level (EL.b)

Roughness

Output data

NPSH

Description

Calculates the available NPSH (Net Positive Suction Head) of a pump. Given the water temperature, flow rate, suction pipe characteristics, and the elevations of the sump water level and the impeller axis, this calculation determines the available NPSH.

NPSHNPSH

Input and output parameters table:

Parameter
Standard Units
Description
Temperature ($T$)
°C
Water temperature
Flow ($Q$)
L/s
Water flow rate
Diameter ($D_s$)
mm
Suction pipe diameter
Diameter ($D_b$)
mm
Discharge pipe diameter
Length ($L_1$)
m
Suction pipe length
Length ($L_2$)
m
Discharge pipe length
Level ($EL_s$)
m
Sump water level
Level ($EL_b$)
m
Impeller axis level
Roughness ($k$)
mm
Pipe roughness
Available NPSH
m
Calculated available NPSH

References

  • VIANNA, Marcos Rocha. Produção, Reservação e Distribuição de Água. e-book. Belo Horizonte: Bloom, 2021.