  The universality of intermittency in hydrodynamic turbulence is considered
based on a recent model for the velocity gradient tensor evolution. Three
possible versions of the model are investigated differing in the assumed
correlation time-scale and forcing strength. Numerical tests show that the same
(universal) anomalous relative scaling exponents are obtained for the three
model variants. It is also found that transverse velocity gradients are more
intermittent than longitudinal ones, whereas dissipation and enstrophy scale
with the same exponents. The results are consistent with the universality of
intermittency and relative scaling exponents, and suggest that these are
dictated by the self-stretching terms that are the same in each variant of the
model.
