高聚物对方腔自然对流传热与流动特性影响的研究  

Effects of polymers on natural convection heat transfer and flow characteristics in square cavities

作　　者：李亚军 LI Yajun(Northwest Design and Research Institute of China Municipal Engineering Co.Ltd,Lanzhou 730000,China)

机构地区：[1]中国市政工程西北设计研究院有限公司,甘肃兰州730000

出　　处：《区域供热》2023年第6期111-117,共7页District Heating

摘　　要：借助FLUENT数值模拟软件,对水中添加高聚物的方腔自然对流进行研究,主要研究添加高聚物后对水流动和传热产生的影响。通过建立合理的数值模型[,对其进行数值模拟和分析。为了排除在数值模拟过程中不同的瑞利数(Ra数)对结果产生的影响,对数值模型进行网格无关性验证,从而确保每一个Ra数下的研究结果不因网格数的不同而出现偏差。通过改变方腔的尺寸来改变Ra数,Ra数从1×10^(4)到1×10^(9)分为6种工况,不同的Ra数对应不同的流动特性,根据某一特定Ra数下的流动性质即层流或者紊流,建立该Ra数对应的模型,确定溶液的物性参数,在FLUENT软件中设置模型、边界条件等,得出数值模拟结果。通过数值模拟输出结果,如速度场、温度场、Nu数等,得出结论:对于方腔自然对流而言,水中加入高聚物后,溶液的流动加快,但传热能力降低,高聚物起到了减阻、降低传热能力的作用。Natural convection in a square cavity with high polymer added to water is studied by FLUENT software.The main purpose of the study is to investigate the effects of high polymer added to water on flow and heat transfer.Through the establishment of a reasonable numerical simulation,the numerical simulation and analysis are carried out.In order to rule out the influence of different Rayleigh numbers(Ra numbers)on the results of numerical simulation,the grid-independent verification is carried out for the numerical simulation,thus,the results under each RA number are not biased by the grid number.Ra numbers are changed by changing the size of the square cavity.Ra numbers vary from 1×10^(4) to 1×10^(9) under six operating conditions,according to the flow property of a certain Ra number,namely laminar flow or turbulent flow,the corresponding model of Ra number is established,the physical parameters of solution are determined,and the model and boundary conditions are set up in FLUENT software,the numerical simulation results are obtained.The results of numerical simulation,such as velocity field,temperature field,Nu number and so on,draw a conclusion:for natural convection in square cavity,when polymer is added to water,the flow of solution is accelerated,but the heat transfer is reduced,high polymer plays a role in reducing drag and heat transfer.

关 键 词：自然对流 方腔 高聚物 数值模拟 

分 类 号：TK124[动力工程及工程热物理—工程热物理]