Generate system curve

Input data

Flows

Geometric head

Pipe length

Inner diameter

Roughness

Roughness multiplier

Total minor losses coefficient

Temperature

Output data

System curve

Description

Generate the system curve for fluid flowing through a pipeline, accounting for the geometric head, pipe length and internal diameter, wall roughness, minor losses, and water viscosity as a function of temperature.

 

The system curve depicts the relationship between flow rate and total head loss (the sum of distributed and localized head losses), enabling hydraulic system analysis and pump sizing.

 

The formula to calculate the total head loss (in meters of water column) is:

hsys(Q)=hg+hf(Q)+kminorQ2h_{\text{sys}}(Q) = h_g + h_f(Q) + k_{\text{minor}} \cdot Q^2

where:

  • hgh_g is the geometric head
  • hf(Q)h_f(Q) is the distributed head loss, calculated using the Darcy-Weisbach equation
  • kminork_{\text{minor}} is the total minor loss coefficient

Input Parameters

Parameter
Default Units
Description
Flows
-
Series of flow rate values to be analyzed
Geometric head
m
Height difference between the inlet and outlet
Pipe length
m
Total length of the pipeline
Inner diameter
mm
Internal diameter of the pipe
Roughness
mm
Roughness of the internal pipe wall
Roughness multiplier
-
Multiplicative factor applied to roughness
Total minor losses coefficient
-
Sum of localized loss coefficients
Temperature
°C
Water temperature, affecting viscosity

Output Parameters

Parameter
Default Units
Description
System curve
-
Series of total head loss values