Hydraulics & Sizing

Souders-Brown/Fair flooding correlations size tray diameter and % of flood; O'Connell gives overall tray efficiency; dry-hole + aerated-liquid-head gives tray pressure drop; a weep check and downcomer-backup check flag operability limits — all screening-fidelity, published methods (never a vendor-guaranteed rating).

hydraulicsfloodingtrayspacking

Concept

The MESH/rate-based solve gives you the separation; hydraulics and sizing turn that into hardware — column diameter from flooding, tray pressure drop, and the weep/downcomer-backup operability checks that decide whether a tray actually works at that diameter.

Downcomer

h_{dc} = \frac{\Delta P_{tray}}{\rho_L g} + h_w + h_{crest}

From analysis/column_internals.py — Souders-Brown/Fair flooding, tray pressure drop, and the weep check.

The math

Show the governing equations

u_{flood} = C_{SB}\sqrt{\frac{\rho_L-\rho_V}{\rho_V}} \quad \text{(Souders-Brown/Fair)}

E_o = 0.492\,(\mu_L\,\alpha)^{-0.245} \quad \text{(O'Connell overall tray efficiency)}

Execution

Failure codes

Screening fidelity — published correlations (not a vendor-guaranteed rating). Flags rather than errors:

floodingStage running above the design flood margin (or >=100% — actually flooding).

weepingDry-hole pressure drop can't support the clear-liquid head at that turndown.

downcomerClear-liquid backup exceeds half the tray spacing.