granular_screen
Estimate granular packing, hopper discharge, and repose angles using closed-form correlations; each result includes an honest low-high band, no external solver.
Instructions
Closed-form granular/powder-mechanics oracles — banded correlations, NO
external solver (the FreeCAD-free analytic twins the YADE DEM solve is gated
against). These are correlations, not exact theory, so each returns
fidelity='correlation' + an honest [low, high] band; the band IS the oracle.
Dispatch on problem:
'packing' (regime='random_close'|'random_loose'|'fcc'[, coordination]) — monodisperse sphere solid-volume fraction φ. RCP ≈ 0.637 (band 0.60–0.66), the random pile a real settle must hit, well below the crystalline FCC/HCP 0.7405. 'beverloo' (outlet_m, particle_d_m[, bulk_density_kg_m3 | material]) — flat-bottom hopper discharge W = C·ρ·√g·(D−k·d)^2.5 [kg/s]; flow ∝ outlet to the 2.5 power, independent of fill height. 'beverloo_exponent' (outlet1_m, flow1_kg_s, outlet2_m, flow2_kg_s [, particle_d_m]) — recover the log-log flow exponent from two (outlet, flow) points; granular 2.5 (band 2.2–2.8) vs Torricelli 2.0. 'repose' (friction_coeff[, saturation]) — poured-pile repose angle θ ≈ atan(μ) + ±25% band. 'repose_monotone' (mu_low, repose_low_deg, mu_high, repose_high_deg) — the steeper-with-friction monotonicity gate.
SI units (m, kg/m³, kg/s, degrees). Escalate to dem_pack_submit / dem_flow_submit (the real YADE solve) for polydisperse mixes, non-spherical grains, cohesion, or geometry this monodisperse idealization can't see.
Input Schema
| Name | Required | Description | Default |
|---|---|---|---|
| mu_low | No | ||
| regime | No | random_close | |
| mu_high | No | ||
| problem | No | packing | |
| material | No | ||
| outlet_m | No | ||
| outlet1_m | No | ||
| outlet2_m | No | ||
| flow1_kg_s | No | ||
| flow2_kg_s | No | ||
| saturation | No | ||
| coordination | No | ||
| particle_d_m | No | ||
| friction_coeff | No | ||
| repose_low_deg | No | ||
| repose_high_deg | No | ||
| bulk_density_kg_m3 | No |