How to calculate friction coefficient of turbulent flow inside a pipe

- May 26, 2019 at 2:50 pm
  
  Devank12
  Subscriber
  
  Can one explain me how to find out the friction coefficient in flow through pipe using ansys fluent???
- May 26, 2019 at 10:40 pm
  
  Raef.Kobeissi
  Subscriber
  
  ${displaystyle {frac {Delta p}{L}}=f_{mathrm {D} }cdot {frac {rho }{2}}cdot {frac {{langle vrangle }^{2}}{D}},}$
  
  Find Delta P ( Pressure inlet - Pressure outlet) and then formulate an expression in Fluent to calculate fd.
  
  Regards
- January 26, 2020 at 9:08 pm
  
  atulsingh92
  Subscriber
  
  A question here.
  
  v should be velocity magnitude, but how to obtain rho?
  
  Should this be from the reference value? or should be made a report first and then added to this expression?
- January 27, 2020 at 5:36 am
  
  DrAmine
  Ansys Employee
  
  That is the fluid density. Its is available as post processing variable under properties.
- January 27, 2020 at 9:43 pm
  
  atulsingh92
  Subscriber
  
  Another spin off
  
  If the diameter (also L) is in mm (5 mm , for example)
  
  1) Should I mesh/scale 0.01 0.01 0.01 and then give 5 in the formula?
  
  or
  
  2) I do mesh/scale 0.01 0.01 0.01 and then give 0.005 in the formula?
  
  I pretty much need to do a meshscale 0.01 0.01 0.01 because every import from spaceclaim tends to not have my own dimensions.
- January 28, 2020 at 5:53 am
  
  DrAmine
  Ansys Employee
  
  You give the length of your geometry along the mean stream . Check every time the scale size dimensions in Fluent.