Thank you for your previous help. I have finally successfully compiled under LINUX.
Now I have a seeding failure. (You have already foreseen in BUILD FAILED–Error in Build solver - MFiX - NETL Flow Science Software Support (doe.gov) ) 
I have reviewed four relevant posts on the forum but have not found a solution, and “seeding failure” lacks of detailed explanation.
complexr_2024-04-28T214159.876039.zip (46.3 MB)
Phase 2: Number of particles to seed = 10380
|-------------------------------------------------------------------|
| IC Region: 3 |
|-------------------------------------------------------------------|
| Phase | Input | Input | Number of | EPs | Solid |
| ID | Specified | Value | Particles | | mass |
|-------|-----------|-----------|-----------|-----------|-----------|
| 2 | EP_S | 6.10E-01 | 8415 | 4.95E-01 | 1.16E-02 |
|-------|-----------|-----------|-----------|-----------|-----------|
Error from des/generate_particles_mod.f:929
Initial condition 3, Phase 2: Unsuccessful seeding
Please adjust seeding volume fraction, or advanced seeding options (lattice, spacing).
You are trying to seed 10380 particles but only 8415 are being successfully placed.
You have specified a volume fraction of 0.61 which is fairly high. As the message suggests, we can adjust advanced seeding options.
By reducing particle spacing to 0 we can now accomodate 9177 particles:
Phase 2: Number of particles to seed = 10380
|-------------------------------------------------------------------|
| IC Region: 3 |
|-------------------------------------------------------------------|
| Phase | Input | Input | Number of | EPs | Solid |
| ID | Specified | Value | Particles | | mass |
|-------|-----------|-----------|-----------|-----------|-----------|
| 2 | EP_S | 6.10E-01 | 9177 | 5.39E-01 | 1.27E-02 |
|-------|-----------|-----------|-----------|-----------|-----------|
At this point it’s not going to be easy to get more particles into the bed region. You can change the specification of the IC to a particle count of 9177 which is the highest you will be able to achieve, but this is a density lower than 0.61. Or you can increase the height of the bed region, and seed the original 10380 particles as you specified, but over a larger vertical range, and let them settle.
I just realized that your model is only one layer thick:
The diameter of spherical particles is 1e-3 and zmax is 1.1e-3 so there is only room for one particle in the Z direction.
Let’s work out the expected density for such a situation.
For simplicity consider unit spheres packed in a planar arrangement in a hexagonal lattice (as we are doing in this case). To avoid edge effects, let the region be LxLx2 where L is large. (The radius is 1, so the diameter is 2, which is why the box is 2 units deep).
As L goes to infinity, the plane region contains L²/2√3 lattice points (consider the area of the triangle in the hexagonal lattice). Now, at each point we place a unit sphere which has volume 4π/3. So the total volume of spheres is 2L²π/3√3.
The volume of the box is 2L² so the volume fraction of the spheres is π/3√3 which is approximately 0.60. In your case the box is an additonal 10% thicker than the sphere diameter which reduces the maximum achievable density by 1/11 to about 0.549 - this is the highest theoretically achevable in this single-layer formation - note that in addition this will be reduced further due to edge effects.
Hope this helps,
– Charles
Thank you very much for your answer.
Following your guidance, I have made adjustments and the problem has been resolved.
