How to Calculate Back Pressure in a 24" Sparge Pipe?

[subbby]

Hello All,

Problem Statement :

• This is for design of a 24" sparge pipe for transporting hot water (85 deg C) for over 60 ft.
• Asked to calculate the Back pressure

Data :

• Liquid in the pipe: water
• Flow rate : 3010 m^3/hr = 0.83611 m^3/sec
• Pipe Dia : 24" = 2.032 mts
• No elbows throughout 60 ft length

How do I go about this calculation ?

1. Do I first find out if its laminar flow or turbulent flow
2. How to arrive at back pressure equations ?
3. Found a link "www.harcomanufacturing.com/docs/Backpressure%20CalculatorP.xls" : that gives an equation which I have never come across in any internet searches before. Is that how Back pressure is calculated

Background of the problem:
This is for a Rotary Breaker project where we have a 24" Sparge Pipe that is sprays hot water onto the huge chunks of solids being processed inside a rotary breaker. Rotary breakers belong the screening family ; where the machine breaks the solids inside a giant cylindrical section (this project ; 16ft Dia) and keep screening the materials as the go forwards in length. Water is used to form a semi slurry state to help fascilitate the breaking

 

[CWatters]

Not my field at all but..

If the outlet of the pipe is at atmospheric pressure isn't the back pressure at the pump end just the pressure drop down the pipe + atmospheric?

There are online calculators that might help..
http://www.efunda.com/formulae/fluids/calc_pipe_friction.cfm