Tuesday, 17 January 2012

Glass properties.

The solar energy that isn't directly transmitted by glass can be partly reflected and partly absorbed. The ratio of each of these components on the incident flux, respectively define the dimensionless factors of reflection (reflectance, ρ), absorption (absorbance, α) and transmission (transmittance, τ) of the glass itself, linked by the equation α + ρ + τ = 1.
The total trasmitted solar radiation normalized by the incoming irradiance is called in Solar Heat Gain Coefficient, SHGC.
It should be noted that absorbance give an amount of heat radiated from the glass.

 The used nomenclature is reported here:
 The governing equation for the energy flow per surface area units at the center of glass is given by :



  1. Great post i must say and thanks for the information. Education is definitely a sticky subject. However, is still among the leading topics of our time. I appreciate your post and look forward to more.

    1. thanks!
      Unfortunately, I don't have time to upgrade this blog because of my work . Many times I tell myself to update and write a post..
      I'll make it :)