学术报告（牛冬娟 5.12）

In this talk, we are concerned with the vanishing viscosity problem for the three-dimensional Navier–Stokes equations with helical symmetry, in the whole space. We choose viscosity-dependent initial data u_{0,\nu}with helical swirl, an analogue of the swirl component of axisymmetric flow,of magnitude O(\nu) in the L_2 norm; we assume u_{0,\nu}→ u_0 in H_1norm . The new  ingredient in our analysis is a decomposition of helical vector fields, through which we obtain the required estimates. It is a joint
work with Quansen Jiu (CNU), M. Lopes and H. Lopes (Brazil)