The radiant interchange within a diffuse conical cavity has been formulated without approximation for both cases of prescribed wall temperature and prescribed wall heat flux. Highly accurate numerical solutions have been obtained for a wide range of cone opening angles and surface emissivities. Results are presented for the radiant efflux from the cavity as a whole and also for the distributions along the cavity surface of such quantities as the apparent radiant emittance, local heat flux (for prescribed surface temperature), and temperature (for prescribed heat flux). A comparison with the approximate analysis of Gouffe disclosed large errors in this prior work.
E. M. SPARROW and V. K. JONSSON, "Radiant Emission Characteristics of Diffuse Conical Cavities," J. Opt. Soc. Am. 53, 816-818 (1963)