Biot Number Calculator

Check lumped capacitance validity

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Biot Number

Check lumped capacitance validity

$$Bi = \dfrac{h L_c}{k}$$Lumped valid if Bi < 0.1

$L_c=V/A_s$. Sphere: $r/3$; cylinder: $r/2$; plane wall: $L/2$. If $Bi < 0.1$, object is spatially uniform.

h (W/m²·K)

L_c (m)

k (W/m·K)

All fields required; k nonzero.

Biot Number

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