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Step 1 — Material data

Material mass flow M kg/h Known

Material density ρ₁ kg/m³ Known

Specific heat Cp kJ/(°C·kg) Known

Initial temp t₀ °C Known

Final temp t₁ °C Known

Secondary steam latent heat r kJ/kg Look-up table

Secondary steam temp T °C Known

Secondary steam density ρg kg/m³ Look-up table

Selected diameter D' m Custom

Liquid residence time t min Design

Step 2 — Self-evaporation & steam flow

VL = M/ρ₁ m³/h

M' = M·Cp·(t₀−t₁)/r kg/h

V = M'/ρg m³/h

U = 0.0512((ρ₁−ρg)/ρg)^0.5 m/s

D = (V/(3600·0.785·U))^0.5 m

Ua = V/(3600·0.785·D'²) m/s

HL = VL·t/(47.1·D'²) m

HG (if 0.1D<0.15, HG=0.15+1.2D, else 1.3D) m

H = HL + HG m

Formula condensed from industrial practice. Always confirm selected D' ≥ calculated D.