Modulated Traveling Waves in Binary Fluid Convection in an Intermediate-Aspect-Ratio Rectangular Cell

Abstract

The mechanism of the transition from the conductive state to the localized traveling wave (LTW) near the onset of binary fluid convection in a rectangular cell with the intermediate aspect ratio r=12 and the separation ratio 1/J= -0.11 is studied by using a two-dimensional numerical simulation of the full hydrodynamic equations. The result shows that counter­ propagating waves (CPW) are generated and modulated until the system evolves to a spa­ tially modulated traveling wave (MTW) which is called an LTW. This type of spatially and temporally modulated counterpropagating waves (MCPW) is similar to the blinking state observed for very small negative values of the separation ratio and plays an important role in the formation of the LTW.