Phase clustering in a hierarchical ensemble of coupled Van der Pol oscillators

The formation of phase clusters in a hierarchical ensemble of coupled Van der Pol oscillators has been studied. It has been shown that a hierarchically organized ensemble at the dynamic mode demonstrates the formation of phase clusters at each hierarchy level and this is accompanied by the clustering of frequencies corresponding to the spectrum of normal modes. It has been shown that clustering is not destroyed in the case of nonidentity of the eigenfrequencies of the oscillators and the random distribution of their initial phases. In the clustering state, the elements of the ensemble that are at the same hierarchy level have the same phase values.