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Sludge removal device for settling tank (BIOWASSERTRACK®)Atmospheric pressure given altitudeSpecific pump velocityAvailable NPSH calculationDynamic viscosity of atmospheric airDetermination of contact time - Ordinance GM/MS No. 888

Estimation of the required NPSH, using the Thoma factor

Input data

Flow

Manometric height

Pump's rotation

Output data

NPSH

Description

Given the values of flow, manometric head, and pump rotation, this calculation estimates the required NPSH (Net Positive Suction Head). In general, the obtained value is very conservative, ensuring the pump's safe operation.

NPSHNPSH

Input and output parameters table:

Parameter
Standard Units
Description
Flow (QQ)
L/s
Pump flow rate
Manometric height (HH)
m
Pump's manometric head
Pump's rotation (ww)
rpm
Pump's rotational speed
Required NPSH
m
Estimated required NPSH

References

  • VIANNA, Marcos R. Estações Elevatórias de Sistemas de Abastecimento de Água. E-book. Belo Horizonte, 2021.