Vladimir Lebedev, Landau Institute
Correlation functions of the passive scalar advected by a turbulent flow are known to possess an anomalous scaling related to their pumping length. The anomalous scaling is the most conspicuous manifestation of the intermittency characteristic of turbulence. Anomalous behavior of the passive scalar correlation functions can be examined in the framework of the Kraichnan model where the turbulent velocity is assumed to be short correlated in time and to possess Gaussian statistics. Closed equations for the correlation functions obtained in the framework of the model enable to relate the anomalous behavior to zero modes of the operators controlling the equations. Anomalous exponents can be explicitly calculated for different limit cases.