下降液膜的阴影成像法研究以及数值图像处理  

Numerical Image Processing of Shadowgraphs for Falling Film

作　　者：卢川[1] 段日强[1] 姜胜耀[1] 

机构地区：[1]清华大学核能与新能源技术研究院

出　　处：《核动力工程》2008年第3期119-123,共5页Nuclear Power Engineering

摘　　要：下降液膜广泛运用于先进压水堆核电站的安全系统(如AP 1000)和核能海水淡化系统。本文通过阴影成像法技术对下降液膜流动不稳定性进行了实验研究,获得了宽广的下降倾角范围内(β=0°～90°)的液膜扰动波的阴影图片,揭示了重力对于液膜扰动波发展演变的重要影响。运用数值图像处理方法研究了下降液膜扰动波的特性,定量分析了液膜扰动波的发展变化,进一步证明了重力对于扰动波发展演变的重要影响,得到了下降液膜扰动波的4个特征区域,绘制了区域随雷诺数和沿程距离的演化图,揭示了雷诺数对于扰动波区域分布的影响。最后通过频谱分析得到了液膜扰动波的扰动频率,获得了与实验一致的结果。Falling film is widely occurred in the safety system for the Advanced PWR Nuclear Power Plant （e.g. AP 1000） and seawater desalination using nuclear energy. In this paper, the instability of falling film was experimentally studied by Shadowgraph technique. The disturbance wave pattern in a wide range of incline angle （ β=0°～90°） were obtained in shadowgraph format. It is indicated that gravity is important for the development of disturbance waves. And moreover, the numerical image processing was applied to analyze the characteristics of disturbance waves on falling film, the development of disturbance waves was analyzed quantitatively and the importance of gravity for disturbance waves was proved again. The dependence of disturbance wave evolution on Reynolds number and flow distance in the main stream direction was obtained and meanwhile four distinctive regions were unveiled. It is indicated that Re has some influence on the regions distributing of disturbance waves. At last, the frequencies of disturbance waves were obtained by spectrum analysis, which accords with the experimental data.

关 键 词：下降液膜 流动不稳定性 扰动波 

分 类 号：TK124[动力工程及工程热物理—工程热物理]