Pipes For Liquid Calculation

Use Illustration:

Design a Pipe suitable to flow 10m3/h of water (density 1000 kg/m3, viscosity 1 cp) over 10 m length with 3 m elevation rise and having 1 90 degree elbow, 2 globe valves.

Solution:

1. Start by plotting a pressure profile of the system. (i.e. identify the inlet pressures and end pressures required in each section of the pipe) Based on the pressure profile, identify the pressure drop allowable in the pipe section in question. For our case say 40 kPa is allowable . (For more info on pressure profile write in.)
   
   
2. Select the pipe mettalurgy from drop down list.
   
   
3. Enter pipe length.
   
   
4. Click on input piping items and enter 1 90 degree elbow, 2 globe valves, click on calculate total k and click on done. (This is used to calcualate equivalent lengths.)
   
   
5. Enter a guesses pipe internal diameter . 50 mm in this case.
   
   
6. Enter flowarte, density, viscosity and elevation difference.
   
   
7. Click on calculate to analyze the results. In this case the pressure drop is 34 kPa that is within the allowable pressure drop limits and thus this pipe diameter is fine. In case it is not change the pipe diameter to achieve the allowable pressure drop limit.
   
   
8. Based on the pressure profile and design pressure select the pipe thickness i.e. schedule. This is the final design, the diameter and schedule of pipe has been defined. Some select the pipe diameter based on velocity as well.
   

Note: Calculations are valid only for incompressible fluids.