Smoluchowski coagulation equation is a mean-field model describing the evolution of the size distribution of particles driven by pairwise coagulation. The rate of coagulation depends on the size of the merging particles and it can determine the qualitative behaviour of the solutions, such as loss of mass-conservation or the lack of stationary solutions.
In this talk, I will present recent results on the analysis of multicomponent coagulation equations, where the size variable is generalized to a composition vector. In this setting, solutions tend to localize along a line in the multidimensional composition space, as the size increases. This property holds true for a large class of coagulation kernels and it motivates new open problems on the analysis of the underlying stochastic particle system.