Abstract
The present study introduces the expression of the radiative source term in an absorbing and emitting medium, which is caused by the collimated incidence of radiation on boundary surfaces. Three different optical characteristics of the boundary surfaces are considered: (1) both opaque, (2) both semitransparent, and (3) one opaque and the other semitransparent. The study conducted numerical simulation for the excess temperature responses at the incident surface and the nonincident one of a semitransparent medium, which is irradiated by a shortβtime laser pulse. The variables affecting the temperature response include the wavelength of the irradiating laser pulse, the spectral properties of the medium, the optical characteristics of the boundary surfaces, a reference temperature, and a thermal diffusivity. The results show that considerable deviations may be produced if the Planck or Rosseland meanβabsorption coefficient is employed to treat a nongray medium. Thus, it is suggested that spectral band models be used. Β© 2002 Wiley Periodicals, Inc. Heat Trans Asian Res, 31(5): 331β343, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.10040