TRANSPHERE: A simple 1-D spherical continuum radiative transfer code
TRANSPHERE is a simple dust continuum radiative transfer code for spherically symmetric circumstellar envelopes. It cannot, however, deal with scattering. It only handles absorption/re-emission. But it computes the dust temperature self-consistently. This code is delivered as-is, with no guarantee that it works properly.
The purpose of the code was originally to have a super-robust and fast radiative transfer method for AGB shells and such. Later I programmed RADMC, which is of course much more versatile. But if you really have just a spherically symmetric problem and you are not too concerned with scattering, then it may be easier to use a simple code such as TRANSPHERE than to use a monster like RADMC.
The method used by TRANSPHERE is a variable eddington factor method. It is described in detail in the paper by Dullemond, van Zadelhoff & Natta (2003), although there it was used and developed for 1-D vertical disk structure models. TRANSPHERE is very much the same, but just for a different coordinate system (spherical coordinates), without the vertical structure iteration and for the case of a central source (the star). But the method of radiative transfer is identical.