  We present multidimensional non-LTE radiative transfer models of hydrogen and
helium line profiles formed in the accretion flows and the outflows near the
star-disk interaction regions of classical T Tauri stars (CTTSs). The
statistical equilibrium calculations, performed under the assumption of the
Sobolev approximation using the radiative transfer code TORUS, has been
improved to include He I and He II energy levels. This allows us to probe the
physical conditions of the inner wind of CTTSs by simultaneously modelling the
robust wind diagnostic line He I (10830) and the accretion diagnostic lines
such as Pa-beta, Br-gamma and He I (5876). The code has been tested in 1 and
2-D problems, and we have shown that the results are in agreement with
established codes. We apply the model to the complex flow geometries of CTTSs.
Example model profiles are computed using the combinations of (1)
magnetospheric accretion and disc wind, and (2) magnetospheric accretion and
the stellar wind. In both cases, the model produces line profiles which are
qualitatively similar to those found in observations. Our models are consistent
with the scenario in which the narrow blueshifted absorption component of He I
(10830) seen in observations is caused by a disc wind, and the wider
blueshifted absorption component (the P-Cygni profile) is caused by a bipolar
stellar wind. However, we do not have a strong constraint on the relative
importance of the wind and the magnetosphere for the `emission' component. Our
preliminary calculations suggest that the temperatures of the disc wind,
stellar wind and the magnetosphere cannot be much higher than ~10,000 K, on the
basis of the strengths of hydrogen lines. With these low temperatures, we find
that the photoionzation by high energy photons (e.g. X-rays) is necessary to
produce He I (10830) in emission and to produce the blueshifted absorption
components.
