DES Length Scale,grid spacing,delta max

behest · January 27, 2014, 08:11

Hello all,
I want to compute delta x (distance between two cell points) in a 3D simulation. Actually, I want to caclucate DES Length Scale and maximum grid spacing is a important parameter to calculate. Actually, 3 grid spacing is needet to calculate in 3D problem and the maximum of them is used in DES Length Scale calculation. My problem is how can I find the grid spacing for each cells. Please help me

behest · February 5, 2014, 15:29

I think that the best way is writting a udf which computes the length scale.
the length scal equation is:

L_s=sqrt(k)/(Bs*delta_max*C_des*w)
Bs=0.09 , C_des=0.61
k=turbulent kinitic energy
w=specific dissipation rate
delta_max=max(delta_x,delta_y,delta_z)

may I ask you which macros should be used?

January 27, 2014, 08:11	DES Length Scale,grid spacing,delta max	#1
behest Member Ali.E Join Date: Sep 2010 Location: Lisboa Posts: 83 Rep Power: 17	Hello all, I want to compute delta x (distance between two cell points) in a 3D simulation. Actually, I want to caclucate DES Length Scale and maximum grid spacing is a important parameter to calculate. Actually, 3 grid spacing is needet to calculate in 3D problem and the maximum of them is used in DES Length Scale calculation. My problem is how can I find the grid spacing for each cells. Please help me

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
y+ and u+ values with low-Re RANS turbulence models: utility + testcase	florian_krause	OpenFOAM	114	August 23, 2023 06:37
Problem of simulating of small droplet with radius of 2mm	liguifan	OpenFOAM Running, Solving & CFD	5	June 3, 2014 03:53
Force can not converge	colopolo	CFX	13	October 4, 2011 23:03
On the damBreak4phaseFine cases	paean	OpenFOAM Running, Solving & CFD	0	November 14, 2008 22:14
Could anybody help me see this error and give help	liugx212	OpenFOAM Running, Solving & CFD	3	January 4, 2006 19:07

February 5, 2014, 15:29		#2
behest Member Ali.E Join Date: Sep 2010 Location: Lisboa Posts: 83 Rep Power: 17	I think that the best way is writting a udf which computes the length scale. the length scal equation is: L_s=sqrt(k)/(Bsdelta_maxC_des*w) Bs=0.09 , C_des=0.61 k=turbulent kinitic energy w=specific dissipation rate delta_max=max(delta_x,delta_y,delta_z) may I ask you which macros should be used?