摘要
搅混格架-组件之间的横向交混研究对于燃料组件创新设计有着重要的意义。本文采用粒子图像测速(PIV)技术测量了两个5×5格架-组件之间的横流。组件上各布置了1种搅混格架,两种格架的条带高度之比为1.744,搅混翼面积之比为1.486,均为倾角29°的分裂式搅混翼。格架轴向排布有两种:条带轴向中心对齐,格架Ⅱ条带顶端和格架Ⅰ条带中心对齐。实验测量了常温、常压下格架下游1.8D_(h)~25D_(h)组件交界处的横流,雷诺数为13200。实验结果表明,组件交界子通道内横流强度以及组件交界子通道和两侧子通道之间的流场都受到格架排布、搅混翼排布的影响。格架轴向高度差越大,组件交界和两侧子通道之间的交混越不均匀。总地来说,排布B中组件交界子通道内的局部横向交混和组件之间的横流交混比排布A更强。
One of the most important components in PWR fuel assembly is spacer grid and mixing vane attached to grid strap has a significant influence on mixing effect in rod bundles.The analysis of crossflow mixing between rod bundles is of great importance to innovative design of fuel assembly,especially for bundles with mixing vane grids(MVGs).Using particle image velocimetry(PIV)technology and MIR method,this paper obtained cross flow in the lateral planes downstream two 5×5 rod bundles.There were two types of MVGs in the experiment,namely MVGⅠand MVGⅡ.The MVGs were installed on the bundles respectively with MVGⅠon the left and MVGⅡon the right.The geometrical parameters of these two types of MVGs were different but both the mixing vanes were split-type with the bending angle of 29°.Besides,the ratio of strap height of two grids was 1.744 and the ratio of surface area of mixing vanes was 1.486.Considering the non-uniformity of lateral flow field between rod bundles caused by height difference of grids,two kinds of arrangements of MVGs were chosen:1)The axial centers of two straps were in alignment;2)The axial center of MVGⅠstrap was aligned with the top of MVGⅡ.The cross flow in the inter-assembly area was measured in the lateral planes of 1.8D_(h)-25D_(h)downstream MVGs.The measurement was conducted under condition of room temperature and atmospheric pressure.To quantify the mixing effects induced by MVGs,cross-flow intensity in the gap between inter-assembly area and its adjacent subchannels and secondary-flow intensity in the inter-assembly subchannels were calculated.The results showed consistency in crossflow trend at different Reynolds numbers,thus the experimental data at a Reynolds number of 13200 were used for analysis.The experimental results indicated that the mixing vane pairs in the interassembly subchannel induced vortices which turned to inter-subchannel cross flow and enhanced the lateral mixing between bundles.The results also showed that the secondary-flow intensity within the inter-assembly subchannel and cross-flow mixing between inter-assembly area and the adjacent subchannels were both effected by axial location difference of MVGs and the arrangement of mixing vanes.The larger the axial height difference of the MVGs,the more uneven the cross flow mixing between the inter-assembly area and the adjacent subchannels.In general,the local cross-flow mixing within the inter-assembly subchannels and cross-flow intensity between assemblies downstream the Btype arrangement of MVGs were stronger than A-type.
作者
蒋理
单建强
周杉
邹逸翔
郭俊良
桂淼
JIANG Li;SHAN Jianqiang;ZHOU Shan;ZOU Yixiang;GUO Junliang;GUI Miao(State Key Laboratory of Multiphase Flow in Power Engineering,Xi’an Jiaotong University,Xi’an 710049,China)
出处
《原子能科学技术》
北大核心
2025年第2期337-347,共11页
Atomic Energy Science and Technology
关键词
粒子图像测速
搅混格架
组件间横流
particle image velocimetry
mixing vane grid
inter-assembly cross flow
作者简介
通信作者:桂淼。
