Estimation of friction factor
 

i have internal pipe flow simulation
the working fluid is water
i want to plot the relation between friction factor [fr] and Reynolds number [Re] by this formula: fr=64/Re

can i added this equation to ANSYS FLUENT


Regards

Plotting f = 64/ Re is something you can do in Excel. You don't need Fluent for this. I'm not sure you are asking the right question.

Replay
 

Dear LuckyTran
i can added f = 64/ Re using solidworks flow simulation but i want to added it
in ANSYS FLUENT


yes i agree with you i can use Excel for insert the Darcy - Weisbach equation which is
f = 64/ Re for laminar internal pipe flow but i interested in CFD code more than excel


Regards

Dear Amar,

You must have a range of Reynolds number with you I assume. So run the simulations at various Reyonlds number. Get the friction factor from Fluent. You may use various analytical relations like f=delta P*D/(L*0.5*rho *V*V) and then compare the 64/Re with this output from Fluent.

repay
 

Dear Shamoon thank you very much but i don not know how to added equation
to ANSYS FLUENT so that i can use it to estimate friction factor for various Re


Regards

You do not need to add any equation to Fluent. You already have parameters that you will put in excel to get a curve. You have Reynolds number from which you get velocity and you put this velocity into Fluent as velocity inlet. Then after running simulation you will get delta p (from Fluent) , you have L you have D you have density of fluid and you have velocity. Do it for all Reynolds number and get a curve. Compare this with 64/Re

The point of CFD is to solve for f (really solve for pressure drop). If you are specifying f, then you shouldn't be doing CFD but something simpler.