k Wall function using a fixed gradient

agustinvo · September 16, 2014, 10:27

Good afternoon,

during my project I have to implement as a boundary condition for the turbulent kinetic energy:

$\frac{\partial k}{\partial n} =2 \frac{k}{\delta}$

but every wall function I have checked they use a fixed value instead of a gradient. I would like to know if there is a simple way to reach it, or if I have to use a fixedGradient BC and modify it (I have been told that to implement this new wall function is not the best idea)...

Any suggestions? Thanks in advance!

mohsen cheraghi · September 16, 2014, 13:16

Quote:

Originally Posted by agustinvo

Good afternoon,

during my project I have to implement as a boundary condition for the turbulent kinetic energy:

$\frac{\partial k}{\partial n} =2 \frac{k}{\delta}$

but every wall function I have checked they use a fixed value instead of a gradient. I would like to know if there is a simple way to reach it, or if I have to use a fixedGradient BC and modify it (I have been told that to implement this new wall function is not the best idea)...

Any suggestions? Thanks in advance!

Hi,
For velocity, there are a partial slip boundary condition which is in the form. Maybe you can start with it and modify it for scalars.
bests.

September 16, 2014, 10:27	k Wall function using a fixed gradient	#1
agustinvo Senior Member Agustín Villa Join Date: Apr 2013 Location: Alcorcón Posts: 313 Rep Power: 15	Good afternoon, during my project I have to implement as a boundary condition for the turbulent kinetic energy: $\frac{\partial k}{\partial n} =2 \frac{k}{\delta}$ but every wall function I have checked they use a fixed value instead of a gradient. I would like to know if there is a simple way to reach it, or if I have to use a fixedGradient BC and modify it (I have been told that to implement this new wall function is not the best idea)... Any suggestions? Thanks in advance!

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Wall function for velocity?	johnblund	OpenFOAM	3	September 6, 2022 07:22
Natural convection in a closed domain STILL NEEDING help!	Yr0gErG	FLUENT	4	December 2, 2019 00:04
Problem creating a new Wallfunction on OF 2.2 !	fredo490	OpenFOAM Programming & Development	8	July 22, 2014 05:16
Problem with rhoSimpleFoam	matteo_gautero	OpenFOAM Running, Solving & CFD	0	February 28, 2008 06:51
Quick Question - Wall Function	D.Tandra	Main CFD Forum	2	March 16, 2004 04:29