EFFECT OF POROUS STRUCTURES ON CHAOTIC BEHAVIORS OF THERMAL CONVECTION IN POROUS MEDIA

点击翻译按钮获取中文摘要

An experimental and numerical study has been made on the effect of inertia force on the chaotic behaviors of thermal convection in porous meida. The existence of the microscopic chaos of the order of the porous structures was experimentally and numerically confirmed. The Lvapunov exponent distributions around the microscopic structures indicate the local inertial effect due to the expansion and contraction of the microscopic flow passages yields the microscopic chaotic behaviors, which are different from the macroscopic chaotic behaviors due to the potential instability of the thermal boundary layeres caused by the buoyancy. Further it is indicated that the local entropy generation becomes large at the locations where the Lvapunov exponent becomes relatively less, which will be of very interest since the chaotic behaviors will be fundamentally suppuressed in the pattern selection or pattern formation mechanism. The confirmtion of the microscopic chaos will also be of interest in connecton with the concept of the inverse cascade process from the small-scale to large-scale motions.