Two-dimensional thermal convection in a system of two immiscible liquids heated from below is studied experimentally and numerically. Convection in the two-layer system is characterized by two distinct coupling modes between the layers. They are mechanical coupling and thermal coupling. These two coupling modes are visualized experimentally and found to be in reasonable agreement with numerical simulations. When buoyancy forces in both layers are of similar strength, thermal coupling is preferred. The mechanical coupling mode dominates when the buoyancy forces are very different in both layers.

Issue Section:
Natural and Mixed Convection
Keywords:
Enclosure Flows, Flow Instability, Flow Visualization
Topics:
Convection, Buoyancy, Computer simulation, Flow (Dynamics), Flow instability, Flow visualization
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