A Note on the Numerical Evaluation of Thermal Radiation Characteristics of Diffuse Cylindrical and Conical Cavities

Presented a re methods that avoid the need to em ploy an extrapolation technique in the region of the criti ca l points for evaluation of the apparent e mmissivity of diffuse cylindrical and conical cavities. The methods involve appropriate s ubstitutions in the integrands of integral equations that are used in a nalytical so lut ions for determ ining the therm al radiation characteri sti cs of diffuse and conical cavi ti es. Equations for ei ther iso thermal or noni sothermal surface temperature conditions are provided in a direc t fo rm for computations. N ume rical results are presented for a general linear tem pera ture d is tribution along the length of a cylindrica l cavity. T he method is equally app licable for the solut ion of othe r problems in integral eq uations where discont inuiti es are e ncountered.