An Experimental Study of the Wave Number Selection for the Finite Amplitude Rayleigh Convection

[摘要] Laboratory experiments have been made to investigate the dependence of finite-amplitude Rayleigh convection cells on the initial conditions of the system. Controlled perturbations with prescribed width-depth ratios were introduced into the fluid (silicon oil) confined in a box which had a small breadth. Subsequent evolution and final steady flows at the Rayleigh number of approximately 45 Rc were observed, where Rc is the critical Rayleigh number. It was found that "two-dimensional" convection cells showed tendencies to adjust their sizes toward the vicinities of the width-depth ratio of 2.3, provided their initial width-depth ratios were outside the range between approximately 2 and 3.

[学科分类] 大气科学