LBM for Poiseuille flow

Hello everybody

I wrote a D2Q9 LBM code in fortran for simulating horizontal poiseuille flow due to pressure gradient but my outputs are unstable. Characteristics of flow are as follow:
H(in x-direction) = 5m
Y(in y-direction) = 0.5m
nu = 10^-6 m2/s
P_inlet = 150 Pascal
P_outlet = 100 Pascal
Could anybody help me about how to input this parameters in the code so that the results be stable??

Thanks
Jazayeri

Hi, i got the same problem here. The output for poiseuille flow was NaN.

hiiii.would you please share your code here?