Applied Hydraulics Homework Problem October 16, 2001
A water supply distribution system for an industrial park is schematically shown in the figure below. The demands on the system are currently at junctions C, G, and F with flow rates given in liters per second. Water enters the system at junction A from a storage tower on a hill. The water surface elevation in the tower is 50m above the ground surface in the industrial park. All pipes are cast iron with lengths and diameters are provided on the table below.
The final solution is shown in the table below.
Applied Hydraulics Homework Problem October 16, 2001
Obtain or write software appropriate for solving pipe networks. You may use WaterCAD or write your own program using FORTRAN or Excel. Answer the following questions by performing a computer analysis of the pipe network described above.
Perform a network analysis (determine flows) for the system above using a computer analysis. Compare your answers with those listed on the attached page. Are there any discrepancies? Comment on these if there are any.
What would happen to the flow rate in pipe EF if the friction factor were reduced? What would happen to the pressure at F? Reduce the friction factor (f) from 0.021 to 0.014 and perform a new network analysis on your computer. Did you reason correctly? Now restore EF to its original friction factor.
What would happen to the flow rate in pipe EF if the diameter were cut in half? What would happen to the pressure at F? Estimate the magnitude of these changes. Reduce the diameter of pipe EF by half and perform a new network analysis on your computer. Did you reason correctly? Now restore EF to its original diameter.
What would happen to the pressure at point F if the demand for water at that point doubled? Estimate the magnitude of this change. Increase the inflow at point A to conserve mass. Perform a new network analysis. Did you reason correctly? Restore the network to its original configuration.
In the example in class, we determined that the pressure at point F would be too low to satisfy the customer. What system changes could be made to raise the pressure at junction F? (Hint: Examine the components of the Darcy-Weisbach equation, which was used to compute headloss).
Using your computer software, determine if your suggested changes for increasing the pressure at junction F would work.