The paper presents a mean-field model for large-scale flows in convection zones of the Sun and solar-type stars. The model extends former differential rotation models by allowance for variations of the flow with time and its deviation from axial symmetry. The model is realized as a numerical code, which combines the spectral method of decomposition in spherical functions with second-order accurate finite-difference method in time and radius. First computations show close agreement of the axially symmetric part of the computed flow with helioseismological detections of differential rotation and meridional circulation. Patterns of the time-decaying non-axisymmetric flow computed with the model qualitatively agree with the Rossby waves observed on the Sun. The paper also formulates a problem for further development of the large-scale flow theory.
L. L. Kitchatinov (Wed,) studied this question.