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Reply To: Low Re flow inside Microchannel


Adrian, thanks for the feedback.

It was actually a RAM issue, as the number of voxels was crossing 1e7. I previously set my domain size excessively high compared to the length scale. However, even after fixing that, I am getting another error. Please, see the snapshot of error message here:

The log file is here:

Apart from the error, several key things to be concerned about for me:

1. My time step (del_t = 5.4803e-10) is very small, which I cannot control because it is automatically calculated based on relaxation time (0.53) and del_x = L/N = 9e-7 (because of very small characteristic length L = 136 microns and resolution N = 150). Consequently, my lattice velocity(U*del_t/del_x) is verysmall at Re=0.1, where U = Re*viscosity/L = (0.1*1.5e-5)/(136e-6). Is there any way to reduce the time step hence the lattice velocity? And hence, make the time propagation faster?

2. My case is similar to the cylinder3d case, the difference is instead of a single cylinder at the center, I have a bunch of small cylinder-like structures on the floor with an approximate diameter of 3 microns each, where my channel dimension is about 400*136*136 micron^3. In my understanding, the resolution needs to be big to resolve the structures on the floor. So I set N=150. Let me know if my understanding is incorrect about the resolution requirement. A snap of the geometry is here: