INERTIAL AND DISSIPATIVE RANGE INTERMITTENCY AT HIGH REYNOLDS-NUMBERS

This talk deals with probability density function (pdf) of longitudina l velocity differences, namely delta upsilon = upsilon(r)(x + r)-upsil on(r)(x) where upsilon(r) is the component of the velocity upsilon alo ng r. These pdfs evolve from a gaussian shape for large scales r, to a strongly non gaussian one with reinforced tails (intermittency) for r dose to the dissipative length. Recently some light was put on this e volution by a theory which takes into account the finite value of the Reynolds number. In some sense, intermittency could be a finite Reynol ds effect.