Enter the flow rate and the pipe diameter into the calculator to determine the flow factor. The flow factor is a dimensionless number that characterizes the flow velocity relative to the pipe cross-sectional area.

Flow Factor Formula

The following formula is used to calculate the flow factor.

FF = frac{4 cdot Q}{pi cdot D^2}

Variables:

  • FF is the flow factor (dimensionless)
  • Q is the flow rate (cubic meters per second)
  • D is the pipe diameter (meters)

To calculate the flow factor, multiply the flow rate by 4, then divide by the product of pi and the square of the pipe diameter.

What is a Flow Factor?

The flow factor is a dimensionless value used in fluid dynamics to describe the relationship between the flow rate through a pipe and the cross-sectional area of the pipe. It provides an indication of the velocity of the fluid relative to the size of the pipe, which can be important for determining whether the flow is laminar or turbulent, and for calculating pressure drops and other hydraulic parameters.

How to Calculate Flow Factor?

The following steps outline how to calculate the Flow Factor.


  1. First, determine the flow rate (Q) in cubic meters per second.
  2. Next, determine the pipe diameter (D) in meters.
  3. Next, gather the formula from above = FF = (4 * Q) / (π * D^2).
  4. Finally, calculate the Flow Factor (FF).
  5. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

flow rate (Q) = 0.05 cubic meters per second

pipe diameter (D) = 0.1 meters