k-omega, cross diffusion

February 9, 2005, 18:01

I am trying to implement k-omega turbulence model. For free shear (wake), turbulent visciosity is increasing. I have to increase w porduction but how? adding cross diffusion is not enough. Any help will be appreciated.. thanks

February 12, 2005, 07:25

It would be preferable to use a mixed model of k-w - k-e type (BSL Model) dd nvs

February 12, 2005, 18:19

Thank you very much for responding. I get over the problem by multiplying w production by an artificial constant (between 1-10) that is dependent on the w value and aspect ratio (which affects the diffusion of omega) of the grid cells. But I will definitely start modifying to BSL method. One more general question. How the wake calculations affect the values in the wall boundaries of airfoil? Would the smoothing that I used (made up) affect the solution too much?

February 13, 2005, 10:23

Hello, Emre I am very busy, therefore i will answer you a later. But I think that the paper of Balakumar(**) can bring brief replies to you se you soon dd ** : P. Balakumar, Computations of Flow Over a Hump Model Using Higher Order Method With Turbulence Modeling , 43rd AIAA Aerospace Sciences Meeting and Exhibit, Reno, Nevada, AIAA 2005-1270, January 10-13, 2005, pp. 20

February 13, 2005, 17:24

Thank you dd. I will search for this paper. see you..

February 9, 2005, 18:01	k-omega, cross diffusion	#1
Emre Guest Posts: n/a	I am trying to implement k-omega turbulence model. For free shear (wake), turbulent visciosity is increasing. I have to increase w porduction but how? adding cross diffusion is not enough. Any help will be appreciated.. thanks

February 12, 2005, 07:25	Re: k-omega, cross diffusion	#2
dd Guest Posts: n/a	It would be preferable to use a mixed model of k-w - k-e type (BSL Model) dd nvs

February 12, 2005, 18:19	Re: k-omega, cross diffusion	#3
Emre Guest Posts: n/a	Thank you very much for responding. I get over the problem by multiplying w production by an artificial constant (between 1-10) that is dependent on the w value and aspect ratio (which affects the diffusion of omega) of the grid cells. But I will definitely start modifying to BSL method. One more general question. How the wake calculations affect the values in the wall boundaries of airfoil? Would the smoothing that I used (made up) affect the solution too much?

February 13, 2005, 10:23	Re: k-omega, cross diffusion	#4
dd Guest Posts: n/a	Hello, Emre I am very busy, therefore i will answer you a later. But I think that the paper of Balakumar() can bring brief replies to you se you soon dd : P. Balakumar, Computations of Flow Over a Hump Model Using Higher Order Method With Turbulence Modeling , 43rd AIAA Aerospace Sciences Meeting and Exhibit, Reno, Nevada, AIAA 2005-1270, January 10-13, 2005, pp. 20

February 13, 2005, 17:24	Re: k-omega, cross diffusion	#5
Emre Guest Posts: n/a	Thank you dd. I will search for this paper. see you..

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
overshooting of Omega in SST komega using simpleFoam	cm_jubayer	OpenFOAM	2	June 7, 2020 13:52
Moving mesh	Niklas Wikstrom (Wikstrom)	OpenFOAM Running, Solving & CFD	122	June 15, 2014 07:20
Boundary Conditions for k omega SST	dancfd	OpenFOAM Pre-Processing	0	June 10, 2011 00:25
implementation of diffusion coefficients and use of diffusion coefficients	stephan	OpenFOAM Running, Solving & CFD	0	February 28, 2010 15:30
Species diffusion coefficient	iceabc	FLUENT	1	June 10, 2004 11:04