The heat transfer coefficient (or film coefficient) is the proportionality constant between the heat flux q and the temperature difference $ΔT$ as the thermodynamic driving force for the flow of heat. It is used in calculating the heat transfer, typically by convection.

Calculation of $h_{tr}$ is based on a paper from 2014 by Sujit Purushothaman by the use of the Fourier transformation to convert the two-dimensional problem into a simple one-dimensional problem.

$h_{\mathrm{tr}}$

W/K.m^{2}

$\frac{q}{DeltaT}$ | general formula |

$\frac{\mathrm{Nu}_{\mathrm{L}} k_{\mathrm{gas}}}{L_{\mathrm{char}}}$ | for horizontal plates |

$L_{\mathrm{char}}$

$\mathrm{Nu}_{\mathrm{L}}$

Nusselt number [-]

$T_{\mathrm{surf}}$