Convection in a horizontal fluid layer heated from below is one of models for studying patterns of convection in binary fluid mixtures and has been extensively studied. In this article, the convection structures in a ...Convection in a horizontal fluid layer heated from below is one of models for studying patterns of convection in binary fluid mixtures and has been extensively studied. In this article, the convection structures in a rectangular cell were investigated for the aspect-ratio Г= 12 and the separation ratio ψ = -0.47. Simulations were preformed by solving the hydrodynamic equations using the SIMPLE method. A Counter Propagating Wave (CPW) state was found in binary fluid convection with a periodically horizontal motion of defects, and the pattern dynamics was further discuss.展开更多
The evolution and transition of planar wave trains propagating through defects(obstacles) in an excitable medium are studied. When the frequency of the planar wave trains is increased, three different dynamical regime...The evolution and transition of planar wave trains propagating through defects(obstacles) in an excitable medium are studied. When the frequency of the planar wave trains is increased, three different dynamical regimes,namely fusion, "V" waves, and spiral waves, are observed in turn and the underlying mechanism is discussed. The dynamics is concerned with the shapes of the defects. Circle, triangle, and rectangle defects with different sizes are considered. The increase of pacing frequency broadens the fan-shaped broken region in the behind of a rectangle defect.The increase of width of a triangle defect leads to breakup of wave trains easier while the change of height shows opposite effect, which is presented in a phase diagram. Dynamical comparison on defects with different shapes indicates that the decrease of the defect width along the propagation of wave trains makes the fan-shaped region and the minimal frequency for breakup of spiral both increased.展开更多
基金the National Natural Science Foundation of China (Grant No. 10872164)the Scientific Research Foundation for the Returned Overseas Chinese Scholars, State Education Ministry (Grant No. 220542)+1 种基金the Key Project of Shanxi Education Committee (Grant No.05JK271)the Scientific Research Foundation of Xi’an University of Technology (Grant No.210532).
文摘Convection in a horizontal fluid layer heated from below is one of models for studying patterns of convection in binary fluid mixtures and has been extensively studied. In this article, the convection structures in a rectangular cell were investigated for the aspect-ratio Г= 12 and the separation ratio ψ = -0.47. Simulations were preformed by solving the hydrodynamic equations using the SIMPLE method. A Counter Propagating Wave (CPW) state was found in binary fluid convection with a periodically horizontal motion of defects, and the pattern dynamics was further discuss.
基金Supported by the Natural Science Foundation of Zhejiang Province under Grant Nos.LQ14A050003 and LR17A050001Zhejiang Province Commonweal Projects under Grant No.GK180906288001China Scholarship Council under Grant No.201708330401
文摘The evolution and transition of planar wave trains propagating through defects(obstacles) in an excitable medium are studied. When the frequency of the planar wave trains is increased, three different dynamical regimes,namely fusion, "V" waves, and spiral waves, are observed in turn and the underlying mechanism is discussed. The dynamics is concerned with the shapes of the defects. Circle, triangle, and rectangle defects with different sizes are considered. The increase of pacing frequency broadens the fan-shaped broken region in the behind of a rectangle defect.The increase of width of a triangle defect leads to breakup of wave trains easier while the change of height shows opposite effect, which is presented in a phase diagram. Dynamical comparison on defects with different shapes indicates that the decrease of the defect width along the propagation of wave trains makes the fan-shaped region and the minimal frequency for breakup of spiral both increased.