自然循环蒸汽发生器倒U型管内倒流特性研究

INVESTIGATION ON REVERSE FLOW IN U-TUBES OF STEAM GENERATOR WITH NATURAL CIRCULATION

以自然循环压水反应堆一回路系统的蒸汽发生器为对象,对蒸汽发生器并联倒U型管内单相水发生的倒流机理及其特性进行了分析,确定了倒流发生的条件和范围,以及发生倒流的倒U型管结构等.在此基础上,建立了分析自然循环系统蒸汽发生器倒U型管内单相水倒流的数学模型,并进行了计算,得出了蒸汽发生器倒U型管内正流和倒流流量、正流和倒流管分布等,并使用实验结果对计算结果进行了检验.研究结果表明,倒流对系统的自然循环能力有重要影响.

A theoretical analysis method to investigate the reverse flow of single phase water in inverted U-tubes of a steam generator with natural circulation has been presented. The analysis results show that normal and reverse flow can simultaneously exist in the inverted U-tubes of the steam generator with natural circulation and reverse flow may preferably occur in longer U-tubes. Through the calculation by using the mathematical model, the U-tubes with normal and reverse flow and the mass flow rates in the tubes with normal and reverse flow were determined. The calculated results were verified by the experimental data. It indicates that reverse flow occurred in the U-tubes of the steam generator has great influence on the mass flow rate in the natural circulation system.