自然循环欠热沸腾起始点发生的混沌特性分析  

Characteristic analysis of chaos taking place at the initial point of sub-cooled ONB under natural circulation

作　　者：盛程[1,2] 

机构地区：[1]上海发电设备成套设计研究院,上海200240 [2]华北电力大学核热工安全与标准化研究所,北京102206

出　　处：《黑龙江电力》2015年第2期126-129,共4页Heilongjiang Electric Power

基　　金：国家自然科学基金项目(50976033)

摘　　要：为了更好地掌握自然循环条件下欠热沸腾起始点(ONB)的特性,笔者根据自然循环实验装置的结构布置和参数范围分析了自然循环ONB点的非线性特性,得到了基于混沌理论的自然循环ONB点发生机理,并对实验获得该点发生前后的流量信号进行了定性和定量研究。研究结果表明,自然循环流量时间序列的功率谱在半对数坐标中指数、自相关系数逐渐下降,三维相图表现出了奇怪吸引子的特点。自然循环系统具有非线性混沌特性,即ONB点发生之前的自然对流和单相自然循环现象周期性显著,并伴随强烈随机运动,为一非平衡过程。In other to further master the characteristic of sub- cooled ONB under natural circulation,the author analyzes its nonlinear characteristic on the basis of the structure and parameters of natural circulation experiment device,from the analysis discovering the mechanism based on chaos theory,and makes the qualitative and quantitative research on the flow signal before and after ONB taking place at the experiment point. The research result shows that the power spectrum of the time series of natural circulation flow represents the gradual descending index and self correlation coefficient in semilog coordinate,with 3d phase diagram representing strange attractor. Besides,the system,which has nonlinear chaos,shows an apparent periodicity of natural convection and single-phase natural circulation before ONB taking place,with strong random motion which is an unbalance process.

关 键 词：自然循环 欠热沸腾起始点 非线性 非平衡 混沌 

分 类 号：TK124[动力工程及工程热物理—工程热物理]