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Diesel injector sac pressure calculation

  1. Mar 8, 2016 #1
    I am trying to calculate the nozzle sac pressure required to deliver 60mm3/ms of diesel fuel into a pressurised cylinder (19MPa). The nozzle has 5 delivery holes of diameter 0.157mm and the discharge co-efficient is 0.87.
    The sac diameter= 0.7 mm and the sac volume= 0.12mm3. I have tried to use the equation below:
    Q=Cd x sqrt(2deltaP/rho) x A2/sqrt(1-(A2/A1)^2) ,
    solving for delta P where p2 = 19MPa. p1= unknown (wanted item)
    A2 = Sum of the 5 hole areas
    A1=Sac area
    rho= density of diesel

    However I am getting incorrect answers, is there something I am missing or doing incorrecty?
    Please let me know!
  2. jcsd
  3. Mar 13, 2016 #2
    Thanks for the post! This is an automated courtesy bump. Sorry you aren't generating responses at the moment. Do you have any further information, come to any new conclusions or is it possible to reword the post?
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