# Pressure Loss owing to multiple nozzles

1. Feb 19, 2013

### subbby

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.