Stefan-Boltzman equation

Radiant heat transfer from a surface is governed by the Stefan-Boltzman equation, see Volume 1, Chapter 9. 

The gas temperature will depend on the fuel used and the amount of excess air. For gaseous fuels, around 20% excess air is normally used, and 25% for liquid fuels. Radiant heat transfer from a surface is governed by the Stefan-Boltzman equation ... 

Models to calculate or can be grouped into two approaches. The first and simpler approach is to use the Stefan-Boltzman equation for radiant exchange between opaque gray bodies. Treating the wall and bed medium as two opposing parallel surfaces with... 

FIGURE 10.6 Normalized blackbody radiation for three stars using the Stefan-Boltzman equation to estimate the temperature of the stars. (From Prof. Mike Guidry of the University of Tennessee Knoxville Department of Physics as used in their Astronomy 162 course, http y7csepl0.phys.utk.edu/astrl62/lect/hght/radiation.html With permission.)... 

In Equation (5.8), hcom- is the convection heat transfer coefficient, A is the surface area, Ts is the solid surface temperature and Tb is the bulk fluid temperature. In Equation (5.9), F 2 is the view factor from surface 1 to 2, a is the Stefan-Boltzman constant, ei, e2 are emissivities, T, T2 are temperatures of surfaces 1 and 2 respectively. 

The solar radiation curve was drawn as an approximation from the solar monochromatic emission data and the use of the measured solar temperature of 6000°K in the Stefan-Boltzman radiation equation. 

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