Nonlinear Drift Waves in Shearing Motion of Plasma

A model equation describing the nonlinear transformation of a drift wave and other objects in the shearing motion of plasma is stated on the basis of the equation of continuity that includes a dissipative item with the efficient diffusion coefficient D. The coefficient D is supposed to be practically equal to the turbulence diffusivity in plasma in case of nonlinear saturation. As a result of calculations, it is established that with linear velocity distribution of the shearing motion, the coefficient D satisfies the known dependence on the shear parameter. A possibility to use the above-considered model equation for determination of the turbulence diffusivity in plasma with an arbitrary distribution of the shearing motion velocity is estimated.