Enter the friction factor, the length (m), the inner diameter (m), and velocity (m/s), into the calculator to determine the Pipe Friction Loss. 

Pipe Friction Loss Formula

The following formula is used to calculate the Pipe Friction Loss.

Pfl = f * (L/D) * (V^2 / (2*g))

  • Where Pfl is the Pipe Friction Loss (m)
  • f is the friction factor 
  • L is the length (m) 
  • D is the inner diameter (m) 
  • V is the velocity (m/s)
  • g is the acceleration due to gravity (9.81m/s^2)

How to Calculate Pipe Friction Loss?

The following example problems outline how to calculate the Pipe Friction Loss.

Example Problem #1

  1. First, determine the friction factor. In this example, the friction factor is given as .45 .
  2. Next, determine the length (m). For this problem, the length (m) is given as  10 .
  3. Next, determine the inner diameter (m). In this case, the inner diameter (m) is found to be .6.
  4. Next, determine the flow speed. This is 12 m/s.
  5. Finally, calculate the Pipe Friction Loss using the formula above: 

Pfl = f * (L/D) * (V^2 / (2*g))

Inserting the values from above yields: 

Pfl = .45 * (10/6) * (12^2 / (2*9.81)) = 5.504 (m)

Example Problem #2

Using the same method as above, determine the variables required by the equation. For this example problem, these are as follows:

friction factor = .87

length (m) = 12

inner diameter (m) = 1

velocity (m/s) = 14

Entering these given values and solving gives: 

Pfl = .87* (12/1) * (14^2 / (2*9.81)) = 104.293 (m)