Recent Advances in the Spherical Harmonics Method
نویسنده
چکیده
In his classic work on radiative transfer, Chandrasekhar introduced the discrete ordinates method for solving the integro-di erential equation of radiative transfer; the spherical harmonics method is a spectral analog of this method. Not surprisingly, there is a close connection between the spherical harmonics and discrete ordinates methods. The spherical harmonics method raises some interesting questions. How are the boundary conditions de ned? How can we evaluate the amount of radiation moving in speci c directions if all we know are the moments? What solution method is best? How can the method be applied to more complex models and in more complex geometries? This paper reviews new work on the spherical harmonics method since around 1980 as it applies to these questions.
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