Abstract: Two-dimensional hydrodynamic description is used to study how the solar wind parameters observed at 1 AU, are influenced by the different conditions near the sun and interplanetary corotating interactions. The results show that a perturbation of velocity rather than temperature or density in the propagation region beyond 0.1 AU imposed much greater influence to the solar wind structure.It is unlikely that the corotating interaction would result in the anticorrelation between the solar wind velocity and Mach number as shown by the statistical values averaged over the solar cycle 20.