Effective Absorptances And Emittances Of Opaque Surfaces And Their Impact On Simulations Of Thermal And Energy Performance Of Buildings

On surfaces perfectly flat and smooth, there are no obstacles to the radiant flow. However, typical surfaces of buildings have bumps and hollows that can significantly change the behaviour of them. The real absorptances and emittances resulting from these surface irregularities could be called effective. This paper presents a simple method developed to evaluate these influences.20172023(2008), ABNT-Associação Brasileira De Normas Técnicas NBR 15 575-Edifícios Habitacionais De Até Cinco Pavimentos-Desempenho. Rio de Janeiro(2004) Standard Test Method For Determination of Emittance of Materials Near Room Temperature Using Portable Emissometers, , ASTM C 1371-04(2009) Standard Test Method For Determination of Solar Reflectance Near Ambient Temperature Using a Portable Solar Reflectometer, , ASTM C1549-09Barbirato, G.M., Silva, C.A., Machado, I.B., Oiticica, M.L., Refletância de cores em superfícies construtivas (2000) Anais Do VIII Encontro Nacional De Tecnologia Do Ambiente Construído ENTAC, , SalvadorBerdahl, P., Bretz, S.E., Preliminary Survey of the solar reflectance of cool roofing materials (1997) Energy and Buildings, p. 25Building Energy Software Tools Directory, , www.eere.energy.gov/buildings/tools_directory/alpha_list.cfm, DOE-U. S. Department Of EnergyIncropera, F.P., Dewitt, D.F., (1996) Fundamentals of Heat and Mass Transfer, , (4. ed.). New York. John Wiley and Sons(1983) Simplified Test Method For Emissivity By Infrared Radio Meter, , JIS A 1423Marchetti, B., Candau, Analysis of the radiative behavior of road materials: Principles and measurements of infrared emissivity (2008) Bulletin Des Laboratoires Des Ponts Et Chaussées, 272 (2008), pp. 45-55Seker, D.Z., Tavil, A.U., Evaluation of exterior building surface roughness degrees by photogrammetric methods (1996) Building and Environment, 31, pp. 393-398Sparrow, E.M., Cess, R.D., (1978) Radiation Heat Transfer, , London: Hemisphere Publishing CorpSparrow, E., Jonsson, V., Radiant Emission Characteristics of Diffuse Conical Cavities (1963) Journal of the Optical Society of America, 53, pp. 816-82