“…For more background of this model and related results, we refer to [12,13]. Many results with regard to the ill-posedness have been obtained for some important nonlinear PDEs including the incompressible Navier-Stokes equations [2,15,17], the stationary Navier-Stokes equations [11,14], the compressible Navier-Stokes equations [3,5] and so on.…”