[sourav90]

Good morning all,

I recently started doing Lagrangian Particle Tracking (also known as CFD-DEM), in which I have particles flowing through a nozzle, having same density as of the fluid. My fluid + particle flow system is laminar (experimentally observed), non-Newtonian shear thinning. My particle volume fraction is ~0.005. As far as I have come though the literature, one-way coupling can be applied for volume fraction of 0.00001 in turbulent flows according to On predicting particle-laden turbulent flows.
I am getting the Particle Reynolds number & the Stokes number with the order of magnitude ~10^-16 & ~10^-17 respectively.

I have two questions:

1. Can Particle Reynolds number be nearly zero?
2. What should be acceptable volume fraction of particle in laminar flow (for one- way or two-way coupling), below which the simulation results would not be reliable?

Is there any books, research, review paper that you know might tell about these? Thanks for your time & input!