4 core & 8 core: same 64bit XP, Xeon, x5570, 2.93GHZ
 

for same *.def file, run both on 4 core & 8 core workstation (other config are same: 64bit XP, Xeon, x5570, 2.93GHZ)

see cpu info here: http://picasaweb.google.com/leeruoyu...56084054998514

4 core is converged within 300 iterations, while 8 core not converged within 300

why ? CPU bothers ?

thanks for advice !

version: CFX12 64 bit

It is unusual for adding extra processes to affect the convergence of the simulation. What type of simulation is it?

Glenn Horrocks

thank you !

it is really strange. any random initilization for CFX ? e.g., how solver to kick off the flow with the prescribed turbulent intensity ? In this case, we would always get different results for different run (i do not believe this as when i run 2 time in the same pc, results are same), puzzled ........ slower or faster we should always get the same thing ah ...

Hi,

CFX only uses random numbers (to my knowledge) in modelling lagrangian particles with turbulence and in generating inlet/initial conditions for LES models. I do not know of any other random numbers used in CFX - but I am not a developer so I am only guessing.

You still have not described what you are doing.

Glenn

hi i am doing porous media (seepage flow) problem... i will test another case soon (free surface problem) ...