Coherent dipolar vortices are a universal outcome of injecting linear momentum into a liquid. Once formed, these dipolar vortices can transport mass and momentum over large length scales and are hence a subject matter of intense research work. Using “first principles” classical molecular dynamics simulations, we report for the first time, formation and collision of dipolar vortices in a two-dimensional prototype strongly coupled liquid, namely, the Yukawa liquid. A dipolar vortex is seen to emerge from the self-organization of a sub-sonic jet profile. This dipole is seen to be very robust and, in general, shows a nonlinear relationship between vorticity and stream function. Starting from two jets injecting linear momentum in mutually opposite directions, we report on the centered head-on collisions between two dipolar vortices. Effect of background friction on the dipole evolution is investigated.

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