AC-2751 -- Deriving Radiation View Factors within a Triangular Cross-Section Residential Attic PDF

A complete set of radiation view factors within a triangular, symmetric, cross-section attic space is derived. These view factors allow nodal radiant energy-transfer equations to be solved for radiant heat exchanges between the attic floor, roof sections, endwalls, and soffits. A simplified analysis of radiant and convective heat transfers within an idealized attic space shows radiative heat transfers to be on the same order of magnitude as convective heat transfers. A computer program is available to solve radiation view factor equations for some representative attic configurations. A simple set of nodal radiation heat-transfer equations is also included to demonstrate the application of view factors to an attic floor and two attic roof sections radiating to one another.