Free and printable **Moody diagrams **have been collected for you to print! A Moody diagram or Moody chart is commonly used by engineers to calculate the Darcy-Weisbach friction factor, which is then in turn used to calculate head/pressure loss due to friction in pipes. On the Moody chart the friction factor is shown on the left hand y-axis, the Reynolds number is shown on the x-axis and the relative roughness is shown on the right hand y-axis. For a more thorough view, look at the first diagram below!

In engineering, the Moody chart or *Moody diagram* is a graph in non-dimensional form that relates the Darcy-Weisbach friction factor f_{D}, Reynolds number Re, and relative roughness for fully developed flow in a circular pipe. In fluid dynamics we have to solve problems which involves the use of Darcy-Weisbach friction factor f. Whether the flow is steady or transient we have to use it. If you try to solve this factor directly , much complexity is experienced. For circular pipes the problems can be solved using Swamee- Jain equation but for the other types it is really difficult. in these cases Moody diagram or Moody charts are really handy. Like the ones posted below

However, there are several things to consider. First, both the Reynolds number and relative roughness are unitless values when computed correctly, therefore the Moody Chart is unitless, so the same chart applies to US Customary and SI unit systems. Another common mistake when reading the Moody Diagram is improper interpolation between lines and points. Be aware of the logarithmic nature of the axes and labels values, halfway between the values is not halfway between the points.

All these diagrams are printable and free to be saved and printed! Just click on the images and make your own moody diagrams!