Question 1

Phase-change vs no-phase-change?

Accepted Answer

Phase-change uses shell steam condensation correlations with optional non-condensable derating. No-phase-change uses forced-convection shell-side ho with manual shell fluid properties.

Question 2

Why are some rows hidden on the free tier?

Accepted Answer

Derived geometry, fouling breakdown, shell condensate props, tube-side Re/Pr/h branches, and the full 1/U expansion match the plant Excel template and require a Pro unlock. After Calculate, licensed users see every row in handbook order with formula/selection notes.