Natural Convection Regime

Visualize Grashof/Rayleigh numbers, natural-convection regime, and Nusselt estimate from temperature difference, length, and properties.

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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RayleighGrashofnatural convectionheat transfer

formula

KaTeX rendered

\begin{aligned}\text{Gr = g beta DeltaT L\^{}3 / nu\^{}2}\\[0.35em]\text{Ra = Gr Pr}\end{aligned}

ASCII source

Gr = g beta DeltaT L^3 / nu^2, Ra = Gr Pr

Delta T (K)vertical length L (m)beta (1/K)nu (m^2/s)alpha (m^2/s)k (W/m/K)

Rayleigh Ra

2.873e+8

Grashof Gr

3.950e+8

Prandtl Pr

0.7273

Churchill-Chu Nu

84.1533

h (W/m^2/K)

4.3760

regime

laminar natural convection

L^3 sensitivity

0.1250

buoyancy term

0.8090

Rayleigh thresholds depend on geometry and boundary conditions. Use this as a setup triage before choosing natural-convection correlations or CFD turbulence models.

Rayleigh Grashof natural convection heat transfer