中压沸腾工况相径向分布实验研究

Experimental Investigation of Phase Radial Distribution in Medium Pressure Boiling Flow

采用高温高压单探头光学探针,在中压沸腾工况下进行了局部空泡率与汽泡频率径向分布特性实验研究,并根据探针信号对两相流流型进行了识别,分析了中压沸腾工况下空泡率径向分布与流型的关系。研究结果表明随热平衡含汽率增加,整个直径方向上空泡率分布从近U形向鞍形和弧形发展;汽泡频率则以近U形分布为主;泡状流工况下,空泡率呈U形或近壁区显著高于中心区的鞍形分布,弹状流工况下,中心区空泡率略低于近壁区,整个直径上空泡率呈弧形分布。

This paper investigated the radial distributions of void fraction and bubble frequency and identified the flow patterns based on the lateral measurement in medium pressure boiling flow using high-temperature high-pressure single-sensor optical probe. The relations between void fraction radial distributions and flow patterns in medium pressure boiling flow were analyzed based on the experimental results. Experimental results showed that the lateral profiles of void fraction changed from near U shape towards saddle and arc as the equilibrium quality increased; local bubble frequency mainly distributed in U shape; the lateral profiles of void fraction took near U or saddle shape (local void fraction close to the wall was significantly higher than that in the core region) in bubbly flow; while in slug flow, local void fraction in the core region was only slightly lower than that in the region near the wall, and the lateral profiles took near arc shape.