Nonlinear convective oscillations with different symmetry properties in two-layer systems

•Oscillations with different symmetry properties, have been studied.•Transitions between convective flows have been investigated.•The period of oscillations changes in a non-monotonic way.•Oscillations are observed in a finite interval of the Grashof numbers.

Nonlinear oscillatory convective regimes developed under the joint action of buoyant and thermocapillary effects in the 47v2 silicone oil–water system, are investigated. Transitions between nonlinear flows with various spatial structures have been studied. Specific types of convective oscillations with different symmetry properties have been found. It is shown that the region of convective oscillations is observed in a finite interval of the Grashof number values bounded from below and from above.