Calculate velocity - is correct?

Hello everybody.
I’ve problem with calculate physical magnitudes. I have done simulations for LBM but now I have to move from LBM units to physical.
In script we have:
diam_LBM = 80
max_velo_LBM = 0.025
visc_LBM = 0.01
and now I need a values:
diam_phys = 4 [mm]
visc_phys = 3.5 [mm^2/s]
I have put it to equation:
velo_phys = (diam_LBM * velo_LBM * visc_phys) / (visc_LBM * diam_phys) where velo_LBM = 0.5 * max_velo_LBM
and I have:
velo_phys = 0.175 [m/s]
It is correct? I think it’s not but I haven’t experience with CFD są I’m asking you.
If it is bad, sb can write for me how it should be?
Thank you in advane,
Bartek.