Periodic Steady Vortices in a Stagnation Point Flow II

Steady-state perturbations to a stagnation point flow of the form ${\bf U}=(0,A'y,-A'z)$ are known which consist of a periodic array of counter-rotating vortices whose axes are parallel to the $y$-axis and which lie in the plane $z=0$. A new understanding of how these vortices depend on the supply of incoming vorticity from afar has lead to the discovery of new families of steady-state periodic vortices that can exist in a stagnation point flow. These new flows have a greater variety of structures than those previously known. An understanding of the linkage between the vortices and the weak inflow of vorticity can have important implications for situations where such vortices are observed.