棒束定位格架两相CFD模拟方法研究  

CFD Simulations on Two-Phase Distribution in Rod Bundleswith Grid Spacers

作　　者：李松蔚[1,2] 张虹[2] 姜胜耀[1] 俞冀阳[1] 

机构地区：[1]清华大学工程物理系,北京100084 [2]中国核动力研究设计院核反应堆系统设计技术重点实验室,成都610041

出　　处：《核动力工程》2012年第2期92-96,共5页Nuclear Power Engineering

摘　　要：考虑气泡合并分裂,采用MUSIG模型,对3×3格架内空气-水两相分布进行计算流体力学(CFD)数值模拟研究发现,计算对入口两相分布预计不敏感,但对气泡直径大小敏感;在定位格架下游不远处,空泡份额分布由较小直径气泡起主导作用,格架下游较远处,空泡份额分布由较大直径气泡起主导作用。考虑空气-水两相流量、几何条件和压力对气泡直径的影响,本文提出针对棒束定位格架的数值模拟气泡最大直径设置关系式,并对模型选取和模拟方法给出建议。计算表明空泡份额分布曲线形状与峰值均和实验符合较好,该模拟方法能合理预测复杂通道两相数值分布。Considering the bubble coalescence and break-up,the CFD simulations for air/water two-phase flow in 3×3 rod bundles with grid spacers have been performed with MUSIG model.The simulation is sensitive with the bubble diameter size but not with the inlet void fraction.The small diameter bubbles are the main effect of void fraction distribution nearby the downstream of the space grid,while the large diameter bubbles are main effect of void fraction distribution at the farther downstream of the space grid.Considering the effect of inlet air-water flow quality,geometry and pressure on bubble max diameter,this paper gives a relation for simulating the bubble with maximum diameter based on which is dealt with numerical simulation for rod bundles with grid spacers is set,and the advice of simulation method and model setting is given.The calculation results show that the shape and peak of void fraction distribution accord well with the experiment,and this simulation method can predict rationally the distribution of two phase flow in complicated channels.

关 键 词：定位格架 两相 CFD MUSIG 

分 类 号：TL333[核科学技术—核技术及应用]