滑移流区纤维束蓄热体换热性能数值研究  

Numerical Study on Heat Transfer Performance of Fiber Bundle Regenerator in Slip Flow Region

作　　者：刘燕英 匡荛 张佳钰 LIU Yan-ying;KUANG Rao;ZHANG Jia-yu(School of Energy and Environment,Southeast University,Nanjing,China,210096;State Key Laboratory of Marine Resource Utilization in South Sea,Hainan Unitersity,Haikou,China,570228;Key Laboratory of Cryogenics,Technical Institute of Physics and Chemistry of CAS,Beijing,China,100190)

机构地区：[1]东南大学能源与环境学院,江苏南京210096 [2]海南大学南海海洋资源利用国家重点实验室,海南海口570228 [3]中国科学院理化技术研究所低温工程重点实验室,北京100190

出　　处：《热能动力工程》2022年第6期122-128,共7页Journal of Engineering for Thermal Energy and Power

摘　　要：随着蓄热体基础部件的尺寸细小化,玄武岩蓄热体的纤维直径微小,顺排排列后,内部形成微细流道。为探究微尺度下产生的尺度效应对玄武岩纤维束内部流道流动和传热的数值模拟的影响,建立了蓄热体的二维层流模型。通过Ansys 17.0 fluent中的UDF函数添加了滑移边界条件,以添加滑移边界条件前后的壁面努塞尔数(Nu)减小百分比为评价指标,对比分析二维纤维束微流道的数值模拟中,滑移边界条件对不同工况下流固换热的影响程度。模拟结果表明:随着温度和间距的增大,添加滑移边界条件后的Nu下降程度会增大;随着纤维排数和入口速度的增加,Nu下降程度会减小;纤维束直径d为20μm,排数小于5排,中心间距超过3 d时,添加了滑移边界条件的Nu的降幅达到了1%以上,在数值模拟中不可忽略滑移流区的影响。As the size of the basic parts of the heat storage body becomes smaller,the diameter of basalt regenerator fiber is very small,so that micro channels are formed among fibers in line arrangement.In order to explore the influence of the scale effect generated at the microscale on the numerical simulation of the flow and heat transfer in the internal flow channel of the basalt fiber bundle,a two-dimensional laminar flow model of the heat storage body is established.The slip boundary condition is added to the simulation by the user-defined function(UDF)in Ansys fluent 17.0.Taking the percentage of wall Nusselt number(Nu)decrease as the evaluation index,the comparative analysis method is used to analyze the influence degree of the slip boundary condition on the fluid-solid heat transfer under different working conditions in the numerical simulation of the two-dimensional fiber bundle microchannel.The simulation results show that with the increase of temperature and spacing,Nu decreases more after the addition of slip boundary condition.With the increase of the number of fiber rows and the inlet velocity,Nu decreases less after the addition of slip boundary condition.When the fiber bundle diameter(d)is 20μm,the number of rows is less than 5 rows,and the center distance exceeds 3 d,the decrease percentage of Nu with the slip boundary condition is more than 1%.The influence of slip flow area cannot be ignored in numerical simulation.

关 键 词：纤维束蓄热体 滑移流区 换热性能 数值模拟 

分 类 号：TK16[动力工程及工程热物理—热能工程]