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Local Similarity Theory of Convective Turbulent Layer Using “Spectral” Prandtl Mixing Length and Second Moment of Vertical Velocity
Approximations of the turbulent moments of the atmospheric convective boundary layer are constructed
based on a variant of the local similarity theory. As the basic parameters of this theory, the second moment of vertical
velocity and the “spectral” Prandtl mixing length are used. This specific choice of the basic parameters allows us to consider
the coefficient of turbulent transfer and the dissipation of kinetic energy of the Prandtl turbulence theory as the forms of
the local similarity. Therefore, the obtained approximations of the turbulent moments should be considered as natural
complementation to the semiempirical turbulence theory. Moreover, within the atmospheric surface layer, the approximations
of the new local similarity theory are identical to the relations of the Monin–Obukhov similarity theory (MOST).
Therefore, the proposed approximations should be considered as a direct generalization of the MOST under free-convection
conditions. The new approximations are compared with the relations of the known local similarity theories. The
advantages and limitations of the new theory are discussed. The comparison of the approximations of the new local similarity
theory with the field and laboratory experimental data indicates the high effectiveness of the proposed approach.