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利用CFD软件数值研究了颗粒三维有序堆积多孔介质的对流换热问题.采用颗粒直径分别为14 mm,9.4 mm和7 mm的球形颗粒有序排列构成多孔介质骨架,在多孔骨架的上方有一恒热流密度的铜板.采用流固耦合的方法研究了槽通道内温度分布和局部对流换热系数的分布以及对流换热的影响因素.研究结果表明:热渗透的厚度和温度边界层的厚度在流动方向上逐渐增大,并且随流量的增加而减小;当骨架的导热系数比较高时,对流换热随颗粒直径的减小而略有增大;对流换热系数随聚丙烯酰胺溶液浓度的增大而减小,黏性耗散减弱了对流换热.
The CFD software was used to numerically study the convective heat transfer of three-dimensionally ordered porous media, and the porous media with spherical particles with particle diameters of 14 mm, 9.4 mm and 7 mm respectively was arranged in sequence to form a porous media skeleton above the porous skeleton The results show that the thickness of thermal infiltration and the thickness of temperature boundary layer are the same as that of the flow of heat boundary layer And increases with the increase of flow rate. When the thermal conductivity of the framework is relatively high, the convective heat transfer slightly increases with the decrease of the particle diameter. The convection heat transfer coefficient increases with the concentration of polyacrylamide solution Increase and decrease, viscous dissipation weakened the convective heat transfer.