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subbby
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The following is the advancement of what I discussed in the link https://www.physicsforums.com/showthread.php?p=4274966#post4274966
Problem Statement
To calculate Pump Discharge Pressure, Calculate the wattage for the pump
Data :
Is my approach (mentioned below) correct ?
Pump Discharge Pressure = Pressure Loss owing to flow thru Horizontal Pipe + Nozzle Pressure* Number of Nozzles
Then,
Now calculating Nozzle Pressure ,
Then add ;
Is this approach Correct ? Am I missing something ?
Problem Statement
To calculate Pump Discharge Pressure, Calculate the wattage for the pump
Data :
- Water @ 85 Degree C
- Flow in for 24” pipe : 3010 m^3/hr
- Flow in 8” pipe : 405 m^3/hr
- Total length of pipe = 50ft
- Nozzle Dia : 1"
- Nozzle pressure : 100 psi
- Nozzle Gallons per minute = 119
- Number of Nozzles = 110 (placed equidistant along the length of the pipe)
- Kinematic & Dynamic Viscosity of water can be found on : http://www.engineeringtoolbox.com/water-dynamic-kinematic-viscosity-d_596.html
Is my approach (mentioned below) correct ?
Pump Discharge Pressure = Pressure Loss owing to flow thru Horizontal Pipe + Nozzle Pressure* Number of Nozzles
Then,
- Find Reynolds Number
- Determine if its turbulent or laminar flow?
- Find the relative roughness of the pipe
- Find the friction factor, either from Moody’s chart or Colebrook equation
- Then calculate pressure loss = (fρLV^2)/(D*2) in Pascal
Now calculating Nozzle Pressure ,
- Already given that per nozzle 100 psi. So total pressure loss owing to nozzles; is 100*110 and convert to Pascal units.
Then add ;
- pressure loss (calculated above) with the Pressure loss owing to those 110 Numbers of nozzles...
and, use the above addition and multiply with the flow rate to attain the wattage ?
Is this approach Correct ? Am I missing something ?