Hence, one can immediately obtain a starting value from Figure 3. In this case, then, using , one reads f = 0.04, from the Moody diagram.
Figure 3: The Moody diagram [3].
Figure 4: The experimental setup (Data used in this article were collected by study group 1: Adam Beougher, Andrew Bertsch and Jamie Coffman).
Step 2. Use the value of f from Step 1 to calculate the average volume flow rate of viscous flow using Equation (7).
Step 3. Use this value of the average volume flow rate to calculate the Reynolds number using Equation (9).
Step 4. Use this value of the Reynolds number and the relative roughness to either look up a new value of the friction factor using the Moody diagram, or to calculate it using the Colebrook formula, Equation (10). This completes the first iteration.
The second iteration. The latest value for the friction factor can be used in Step 1 to initiate the second iteration. This iterative process continues until the difference between consecutive estimates of the volume flow rate become so small that additional iterations are unnecessary.
This series of n iterations described above can be summarised in pictorial form as shown below: