  We derive the classical equations of hydrodynamic type (Euler equation and
the continuity equation) from which the Schrodinger equation follows as a limit
case. It is shown that the statistical ensemble corresponding to quantum system
and described by the Schrodinger equation, can be considered as an inviscid gas
obeying the ideal gas law with quickly oscillating sign-alternating
temperature. This statistical ensemble performs the complex movements
consisting of smooth average movement and fast oscillations. It is shown that
average movements of statistical ensemble are described by Schrodinger
equation. A model of quantum motion within the limits of classical mechanics
which corresponds to the considered hydrodynamic system is suggested.
