arXiv subjects

Charles H Aboughantous

Publications and source records attributed to Charles H Aboughantous.

2 recordsLinked to original sources

arXiv2003

A reduced transfer equation in one-dimensional spherical geometry with central symmetry

The transfer equation in spherical geometry with central symmetry, which is a partial differential equation in two variables r and m, is reduced to a one-dimensional transfer equation in r parametric in m. This is done by dropping the angular derivative from the equation in conservation form without impeding the moments of the specific intensity. The justification for this reduction of the transfer equation is demonstrated analytically and numerically. The numerical demonstration is made by comparing the moments, zeroth to fourth, obtained using the analytic solutions in r of both the reduced equation and the transfer equation in conservation form using the discrete ordinates method. The agreement between the two sets of data is perfect within round-off errors.

astro-ph↗

arXiv2002

A two-streams discrete ordinates solution of radiative transfer in 1-D spherical geometry

The analytic solution for the two-streams discrete ordinates equations is carried out on the spatial domain in one-dimensional spherical geometry. The solution satisfies all the physical and the geometric conditions, namely: the natural boundary condition at the surface of the sphere, the symmetry condition at the center and the reciprocity of path. The solution obeys the inverse square law and is finite everywhere in the sphere except at the center. Graphical and numerical data obtained in cold absorbing spheres confirmed the analytical predictions. The conservation of energy is satisfied with high accuracy within round-off errors.

astro-ph↗