  Infrared emission from the dust shell around IRC+10216 is analysed in detail,
employing a self-consistent model for radiatively driven winds around late-type
stars that couples the equations of motion and radiative transfer in the dust.
The resulting model provides agreement with the wealth of available data,
including the spectral energy distribution in the range 0.5--1000 \mic, and
visibility and array observations. Previous conclusions about two dust shells,
derived from modelling the data with a few single-temperature components of
different radii, are not supported by our results. The extended, continuous
temperature and density distributions derived from our model obviate the need
for such discrete shells. The IR properties vary with the stellar phase,
reflecting changes in both the dust condensation radius $r_1$ and the overall
optical depth $\tau$ -- as the luminosity increases from minimum to maximum,
$r_1$ increases while $\tau$ decreases. We find that the angular size of the
dust condensation zone varies from 0.3 arcsec at minimum light to 0.5 arcsec at
maximum. The shortage of flux at short wavelengths encountered in previous
studies is resolved by employing a grain size distribution that includes grains
larger than \about\ 0.1 \mic, required also for the visibility fits. This
distribution is in agreement with the one recently proposed by Jura in a study
that probed the outer regions of the envelope. Since our constraints on the
size distribution mostly reflect the envelope's inner regions, the agreement of
these independent studies is evidence against significant changes in grain
sizes through effects like sputtering or grain growth after the initial
formation at the dust condensation zone.
