热对流环中混沌的控制技术

CONTROLLING CHAOS IN A THERMAL CONVECTION LOOP

本文应用谱展开法将描述一维热对流环中流体层流自然对流循环的质量、动量和能量守恒方程化为一组无穷维的常微分方程组；其一阶模态为自封闭的Lorenz方程。应用线性与非线性反馈控制，通过数值模拟发现混饨的线性和非线性反馈控制技术可以明显改变热对流环中流体的运动特征，达到我们所希望的流型，即增强混沌或抑制混沌。

In this paper, the methods of feedback controlling chaos techniques in a thermal convection loop are studied theoretically. The lorenz equation, the firist mode of a set of infinite dimensional differential equations are obtained by using the Galerkin spectrum method on the masss momentum and energy equations describing the laminar flow in the thermal coflvection loop. It has been found that the flow characteristics of the thermal convection loop are altered significantly by using the linear and nonlinear feedback controller effecting small temperature perturbations in the boundary conditions. The suppressing or enhancing chaos in thermal convection loop are possible. And some desired periodic flow structures can be achieved by using nonlinear feedback controlling techniques.