堵流工况下棒束子通道流场实验与模拟研究  

Experimental and Numerical Study of Rod Bundle Sub-channel Flow Field under Blockage

作　　者：陈登高 毕景良[1] 黄彦平[1] 袁德文[1] 昝元峰[1] 徐建军[1] CHEN Denggao;BI Jingliang;HUANG Yanping;YUAN Dewen;ZAN Yuanfeng;XU Jianjun(Key Laboratory on Nuclear Reactor Thermal Hydraulics Technology,Nuclear Power Institute of China,Chengdu 610213,China)

机构地区：[1]中国核动力研究设计院核反应堆热工水力技术重点实验室,四川成都610213

出　　处：《原子能科学技术》2023年第1期94-103,共10页Atomic Energy Science and Technology

基　　金：国家自然科学基金(12005217);国防科技工业核动力技术创新中心基金(HDLCXZX-2021-025)。

摘　　要：为探究堵流状态下的棒束子通道流场和流量分布特征,本文使用激光粒子测速(PIV)方法对5×5棒束子通道在堵流情况下的流场和子通道流量进行了实验测量,同时使用数值模拟方法进行模拟分析,得到子通道最大堵流比例72%情况下的子通道下游流场以及子通道流量分布数据,结果表明:子通道堵塞会导致对应子通道流速和流量出现明显降低,非堵塞通道的明显加强。对于实验测试的最大72%堵流比例,堵塞物对下游约0.5D范围影响最大,其子通道流速仅有平均流速的约30%,中心堵流子通道流量仅为平均流量的25%左右。使用浸入界面方法模拟了堵流工况,结果表明:该方法能快速有效地模拟子通道堵流情况,堵塞物带来的局部回流是导致堵流件下游0.5D范围内流速过低的主要原因。Experiment study of a 5×5 rod bundle was conducted to investigate the effect of blockage on sub-channel flow field and mass flow rate.A 3×3 block was set in a 5×5 rod bundle with the largest blocking percent of about 72%in the center sub-channel.The flow field from 2D upstream of the blockage center to 5D downstream was measured by particle image velocimetry(PIV)method.Moreover,the mass flow rate of sub-channel was obtained through a numerical integration using PIV results.At the same time,numerical method was used to simulate this phenomena.A self-developed 3D numerical analysis software called KILI V1.0 was used to simulate the blocking case.This software uses the immersed surface technology with Cartesian grid which allows directly using of 3D geometry from CAD software.3D flow field was numerically calculated using NS equations with turbulence modeled by RANS method.Widely used commercial CFD software was also used for simulation to evaluate the uncertainty of the developed software.The obtained PIV results show that the blockage has an obvious effect on the flow field of the blockage downstream.The blocking leads to decrease of velocity in the blocked sub-channel and increase in the non-blockage sub-channel.For the tested 72%percent case,the blockage has a great influence within 0.5D downstream of the blockage.The average velocity within 0.5D downstream is only about 30%of the mean velocity,and the mass flow rate is only about 25%of the theoretical value.The velocity of the unblocking sub-channel increases over 50%,and the flow rate increases 30%from the theoretical value.The experiment result also shows that the effect of blocking decreases to 40%after 1D downstream and slowly recovers to normal flow.Back flow was observed in the center blocking sub-channel closed downstream area.Normalized sub-channel flow rate index was induced to quantify the flow rate diversion from theoretical value.The index shows that the blocking leads to over 1.6 times relative diversion in mass flow rate in the center blocking

关 键 词：棒束子通道流场 棒束子通道流量 堵流 数值模拟 浸入界面方法 

分 类 号：TL334[核科学技术—核技术及应用]