Nontrivial Stationary Vortex Configurations

In the previous chapters, we have discussed nonstationary phenomena associated with the various types of point vortices. These vortices actually play a significant role in the formation of different stationary vortex flows. This chapter is focused mainly on the numerous stationary configurations that contain different types of singularities. Such configurations can include both the usual point vortices and more complicated singularities as well. All these solutions belong to two-dimensional hydrodynamics. In three-dimensional hydrodynamics, more complex configurations appear. In addition, a three-dimensional velocity field can form nontrivial topological vortex configurations, the so-called topological solitons. In these solitons, lines of force in the vortices are linked, which significantly increases their stability and their chances of survival in three-dimensional nonstationary fluid dynamics.