| 摘 要： | The perturbation equation of the Navier-Stokes equation is obtained by superimposing a noise field on to a flow field. Because of the interaction between viscosity and the perturbation displacement,the equation simultaneously the properties of dissipation and dispersion. It reveals the following important physical features of turbulence: the mechanism of transition and intermittency, which arises from a composite spatio-temporai instability mainly due to the interaction between viscosity and positive dispersion; and the relationship between negative dispersion and turbulent energy inversion.
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