Discussion Forum

Hi everyone,

I am very new to COMSOL, but I have a decent amount of experience in fluid dynamics and CFD (mostly Fluent and CFX). I am trying to set-up a simple 2-D laminar flow model on a micro-fluidic channel (a channel with arrays of small pins in it). I am planning on doing a parameteric sweep on geometrical parameters (such as pin angle, height etc) to characterize the flow and optimize the pressure drop in the channel.

My main issue is meshing time. I tried a somewhat simplified geometry to get my feet wet and making sure that I was setting things right, and everything seemed to work, but the meshing time was 30+hrs for an 4E6 DOF mesh, while the solution time was only 15 mins (although I set the residual to 1E-3 since it was only a test). I am running on a relatively powerful desktop with 64GB of RAM and 2x12 core Xeon processors and COMSOL 5.4.

If I understand the meshing nodes correctly, I am setting two sizes, one for the bulk domains and one for the internal and external boundaries, a corner refinement and I am using a free triangular mesh with 3 layers of boundary layers. The resulting mesh quality is quite good I believe (with a minimum element quality of ~0.5 and avg ~0.9) but again the generation time seems too long. I would like to speed it up as much as possible since I would like to explore a large parameteric space for the sweep.

Is this somewhat normal or am I doing something wrong? Does the meshing algorithm run in parallel by default? Can I enable it or are only some of meshing algorithms parallelizable?

Thanks in advance for your help, and let me know if you need more information,

Krsto