%0 Journal Article
%A Joseph H Klems
%B ASHRAE Transactions
%D 1993
%G eng
%N 1
%T A New Method for Predicting the Solar Heat Gain of Complex Fenestration Systems II. Detailed Description of the Matrix Layer Calculation
%V 100
%1 <p>Windows and Daylighting Group</p>
%2 LBL-34716
%X <p>A new method of predicting the solar heat gain through complex fenestration systems involving nonspecular layers such as shades or blinds has been examined in a project jointly sponsored by ASHRAE and DOE. In this method, a scanning radiometer is used to measure the bi-directional radiative transmittance and reflectance of each layer of a fenestration system. The properties of systems containing these layers are then built up computationally from the measured layer properties using a transmission/multiple-reflection calculation. The calculation produces the total directional-hemispherical transmittance of the fenestration system and the layer-by-layer absorptances. These properties are in turn combined with layer-specific measurements of the inward-flowing fractions of absorbed solar energy to produce the overall solar heat gain coefficient.</p><p>A preceding paper outlined the method and provided the physical derivation of the calculation. In this second of a series of related papers the detailed development of the matrix layer calculation is presented.</p>