Drag Force UDF in Non-Newtonian (powerlaw) Fluid

ali hemmati · October 27, 2012, 11:21

Hello,

I am going to simulate the behaviour of micron-sized particles in an non-Newtonian fluid medium. In fact, the flow viscosity follows the "power-law". I know that "DEFINE_DPM_DRAG(Drag_force,Re,p)" can pass the force per mass of each particle to Fluent, and that the returned valuee must be in form of "

".

As you know, in powerlaw fluid, Re is defined as $Re = \rho V^{2-n} d^{n} / m ,$ and

being the particle diameter and

the "consistency index".

The problem is, how does Fluent define Re number? Does Fluent think of Newtonian Re or this definition of Re? Should I pass this Re in "18*Cd*Re/24" or the Newtonian Re?

Thank you!

marcoscp2 · July 6, 2015, 12:16

Were you able to solve your problem?

liliana · March 28, 2019, 13:08

Hi!

Have you guys solved the problem? I am having the same issue here...

October 27, 2012, 11:21	Drag Force UDF in Non-Newtonian (powerlaw) Fluid	#1
ali hemmati New Member Ali Join Date: Mar 2011 Posts: 27 Rep Power: 15	Hello, I am going to simulate the behaviour of micron-sized particles in an non-Newtonian fluid medium. In fact, the flow viscosity follows the "power-law". I know that "DEFINE_DPM_DRAG(Drag_force,Re,p)" can pass the force per mass of each particle to Fluent, and that the returned valuee must be in form of "". As you know, in powerlaw fluid, Re is defined as $Re = \rho V^{2-n} d^{n} / m ,$ and being the particle diameter and the "consistency index". The problem is, how does Fluent define Re number? Does Fluent think of Newtonian Re or this definition of Re? Should I pass this Re in "18CdRe/24" or the Newtonian Re? Thank you!

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Drag force on scaled models.	arunjingade	Main CFD Forum	6	July 1, 2010 08:54
Lift and drag force	Arti	Main CFD Forum	0	April 23, 2009 22:46
Fluid mechanics / drag & lift	Jamcam	Main CFD Forum	0	October 31, 2002 04:39
Terrible Mistake In Fluid Dynamics History	Abhi	Main CFD Forum	12	July 8, 2002 09:11
Airfoil Drag Force	wowakai	Main CFD Forum	3	October 13, 1998 19:27

July 6, 2015, 12:16	Hi	#2
marcoscp2 New Member Marcos Join Date: Nov 2013 Posts: 12 Rep Power: 12	Were you able to solve your problem?

March 28, 2019, 13:08		#3
liliana Member Liliana de Luca Xavier Augusto Join Date: Feb 2013 Posts: 64 Rep Power: 13	Hi! Have you guys solved the problem? I am having the same issue here...