氯碱电解槽内压力波动的混沌分析及流型识别

为研究氯碱电解槽内气液两相流动的压力波动特性和流型特点,对冷模电解槽阳极室内循环板上开口处的压力信号进行了混沌特性分析;利用高速摄像仪照相法及Kolmogorov熵下降法对流动形态进行了识别,绘制了流型图;利用流型图对不同电流密度下的两相流型进行了判定。结果表明,电解槽压力信号的吸引子具有分数维数,当电流密度大于6 kA·m^-2时,Lyapunov指数大于0,说明电解槽内两相流动具有混沌特性;对于测压点位置及电解槽下部,当电流密度小于5 kA·m^-2时,分别为射流充分发展段和孤立气泡流;电流密度为5 ~ 8 kA·m^-2时为射流过渡段和合并气泡流;电流密度大于8 kA·m^-2时为射流的初始段和合并气泡流。

Chaotic analysis of pressure fluctuation and identification of flow regime in chlor-alkali electrolyzer

In order to clarify the pressure fluctuation characteristics and flow patterns of the gas- liquid two-phase flow in the chlor-alkali electrolyzer, the pressure signals at the upper opening of the recirculation plate in the anode chamber of a cold-model electrolyzer were analyzed by using chaos method. The flow patterns were identified by the Kolmogorov entropy descending method and the pictures taken by a high-speed camera. The flow pattern maps were drawn. The flow patterns under different current densities were determined. The results show that, the attractors of pressure signal of electrolyzer have fractional dimension. The values of Lyapunov exponent are greater than 0 when the current density exceeds 6 kA·m^-2. These results demonstrate the gas-liquid two-phase flow in the electrolyzer has chaotic characteristics. For the position of the upper opening of the circulation plate and the lower section of the electrolyzer, the fully developed section of the jet flow and the isolated bubble flow appear when the current density is less than 5 kA·m^-2. The transition section of the jet flow and combined bubble flow appear when the current density is 5－8 kA·m^-2. The initial section of the jet flow and combined bubble flow appear when the current density is greater than 8 kA·m^-2.