Drying Profile Planner

Check whether oven length, line speed, and temperature give the wet film enough dwell to dry, flagging under-cure when residence time falls below the diffusion estimate.

Computes total dwell from oven length and line speed, splits across zones, and compares against a thickness-based diffusion estimate t ≈ thickness² / D_eff with D_eff ≈ 1e-9 × exp((T_oven − T_BP)/30) m²/s. The margin ratio (dwell/required) flags severe under-cure below 0.5×, marginal between 0.5× and 1.0×. Air velocity, humidity, and skin formation are explicitly out of scope — the tool exists for triage and order-of-magnitude sizing before a coating trial.