Abstract: An improved approximation is presented to
accurately predict radiative heat flux and its related quantities such as
emittances and reflectances of anisotropically scattering media. In this method,
the second order Legendre expansion coefficient of the radiant intensity, appearing in equations is approximated by the
zeroth order one,in
form of Here, K
denotes a correction factor and is determined so as to reproduce the
hemispherical emittances of isothermal, gray, Henyey-Greenstein’s scattering
media bounded by a black surface. A value of K
thus determined changes variously with the optical thickness in the range of less than about five, but is
asymptotic to some constant value denoted by An accurate rational approximation
to is derived. The validity of the
present improved approximation
is examined in some pure radiation problems.
Keywords and phrases: radiative transfer,
improved approximation, anisotropically scattering media.
