Details

The heat flux for conductive heat transfer through the skin is equal to the convective heat transfer of the moving air:

,

,

where is heat flux (), and are the inner and outer surface temperatures (°C), is the thermal conductivity of fatty tissue (), is skin thickness (mm), is the convective heat transfer coefficient of air () and is air temperature (°C).

For a calm day, . For a windy day, the convective heat transfer coefficient is a function of wind speed:

,

where is wind speed (m/s).

Reference

[1] T. L. Bergman, A. S. Lavine, F. P. Incropera and D. P. DeWitt, Introduction to Heat Transfer, 6th ed., Hoboken: John Wiley and Sons, 2011.