Practical 3: Friction and Minor Losses in Pipes

Please download this excel spreadsheet to obtain data for this experiment.

You will see that for the major losses, each pipe had three different flow rates passed through it. In each case, the pressure was measured upstream and downstream to determine the overall pressure head loss over the length of the pipe. You will use this to determine the Darcy friction factor, and in turn use the friction factor to determine the relative roughness of the pipe (k/D).

For the minor losses, a single flow rate was passed through the pipe and the pressure was measured upstream and downstream of several typical objects (two valves and an elbow bend). These were all in 25mm galvanised steel pipe. It is important to note that the observed pressure head loss in these cases is due to both the minor loss in the object itself and a small amount of pipe friction. For this reason, you have also been given the length of pipe between the two measurements. You will need to use an appropriate friction factor from your analysis of 25mm galvanised steel pipe in the first part of the experiment (major losses).