低压两相自然循环流动不稳定实验研究

Experimental research on natural circulation two-phase flow instability under low pressure

针对低压工况两相自然循环流动不稳定的边界进行实验研究.根据不稳定起试点的实验段出口干度,结合流动速,确定出不稳定的类型为第一类密度波型不稳定.采用不同的自然循环密度波稳定边界半经验关系式对不稳定起试点进行了判断,实验结果表明,考虑实验装置几何特性的变化,以水为工质得出的稳定边界与实验结果符合较好,而与以氟里昂为工质的稳定边界对应较差.根据实验数据,按照不同的模型,拟合了该实验的密度波型脉动的稳定边界,拟合结果和实验结果误差在15%以内,表明现有的模型是可行的.

Experimental research was conducted on the boundary of natural circulation two-phase flow instability. Steam quality at the test section outlet of the threshold of flow instability was calculated according to flow rate and the flow instability was found to be Type- Ⅰ density wave instability. The experimental results were compared with several density wave oscillation stable boundary correlations. Considering the difference of experimental apparatus, experimental data correlated well for water work fluid and did not fit with correlation for Freon-12 work fluid. With a different model and dimensionless analysis of partial differential, empirical correlations for the threshold conditions of flow instability were given and fit well with experimental data. The error was less than 15 percent, so the modes were found to be doable.