who can help me expain the kqrwallfunction,thanks

hei@ge · October 27, 2011, 00:27

the description for kqrwallfunction as follows

escription
Boundary condition for turbulence k, Q, and R when using wall functions.
Simply acts as a zero gradient condition.
who can tell me what do the Q and R represent? i do not find the paraments of Q,R in my case.

Linse · October 27, 2011, 05:11

I do not know for sure, but I would assume - please check and correct me, if wrong! - that R stands for the Reynolds number.
Q quite often is used for a flux, so it is tempting to assume it is the same here...

Bernhard · October 27, 2011, 09:23

R stands for the Reynolds stress, this is a symmetric tensor. For Q I'm not sure.

boger · October 27, 2011, 10:35

The LRR model, for example, solves an equation for R, which is the Reynolds stress tensor. In turbulence, q is traditionally the square root of k (tke); the qZeta model, for example, solves an equation for q.

October 27, 2011, 00:27	who can help me expain the kqrwallfunction,thanks	#1
hei@ge Member 张德胜 Join Date: Oct 2011 Posts: 71 Rep Power: 15	the description for kqrwallfunction as follows escription Boundary condition for turbulence k, Q, and R when using wall functions. Simply acts as a zero gradient condition. who can tell me what do the Q and R represent? i do not find the paraments of Q,R in my case.

October 27, 2011, 10:35		#4
boger Senior Member David Boger Join Date: Mar 2009 Location: Penn State Applied Research Laboratory Posts: 146 Rep Power: 17	The LRR model, for example, solves an equation for R, which is the Reynolds stress tensor. In turbulence, q is traditionally the square root of k (tke); the qZeta model, for example, solves an equation for q. Mojtaba.a likes this. __________________ David A. Boger

October 27, 2011, 05:11		#2
Linse Senior Member Bernhard Linseisen Join Date: May 2010 Location: Heilbronn Posts: 183 Blog Entries: 1 Rep Power: 16	I do not know for sure, but I would assume - please check and correct me, if wrong! - that R stands for the Reynolds number. Q quite often is used for a flux, so it is tempting to assume it is the same here...

October 27, 2011, 09:23		#3
Bernhard Senior Member Bernhard Join Date: Sep 2009 Location: Delft Posts: 790 Rep Power: 22	R stands for the Reynolds stress, this is a symmetric tensor. For Q I'm not sure.