Radiation-Convection Heat Balance

Compare radiation and convection heat-rate contributions from surface temperature, surroundings, emissivity, and h.

visual calculatorHeat Transfer

Read the flow shape before trusting the number.

This page turns a CFD setup into regime, scale, and dominant-effect cues. Adjust the calculator below and compare the moving graphic with the computed result.

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radiationconvectionheat balancethermal boundary condition

formula

KaTeX rendered

\begin{aligned}\text{Q\_rad = epsilon sigma A (T\_s\^{}4 - T\_sur\^{}4)}\\[0.35em]\text{Q\_conv = h A (T\_s - T\_inf)}\end{aligned}

ASCII source

Q_rad = epsilon sigma A (T_s^4 - T_sur^4), Q_conv = h A (T_s - T_inf)

emissivitysurface T (K)surrounding T (K)area (m2)h conv (W/m2/K)

radiation533.43 W

convection624.00 W

Q_rad (W)

533.427

Q_conv (W)

624.000

Q_total (W)

1157.427

radiation share

46.09%

Radiation becomes nonlinear fast. This helps decide whether a CFD thermal boundary can ignore surface-to-ambient radiation.

radiation convection heat balance thermal boundary condition