对多孔材料强化管内换热进行了数值研究,详细讨论了多孔材料厚度(0≤e≤1)和渗透率(10^-5≤Da≤10)等参数对管内换热特性和压力损失的影响。结果表明:利用多孔材料调整流场分布,剪薄边界层厚度,能够有效地增强管内换热。当Da=10^-4时,管内充分发展Nu数最大能够增至空管时5.5倍左右。但管内压力损失随着多孔材料厚度e的增加或Da数的减小而急剧增大。因此在实际应用中,应采用部分填充多孔材料,文中建议最佳的多孔材料厚度e取0.6左右,此时换热可以得到相当程度的强化,而且压力损失控制在可接受的范围内。
Numerical simulation has been carried out to investigate the heat transfer enhancement in the pipe filled with porous medium and the effect of the thickness(0≤e≤1) and permeability (10^-5≤Da≤10) of the porous medium on the heat transfer and pressure loss in the pipe has been studied. The results show that the flow field can be adjusted and the thickness of boundary layer can be decreased with the porous medium so the heat transfer can be enhanced in the pipe. When Da is equal to 10^-4, the fully developed Nu can be increased to as large as 5.5 times of that without the porous medium. But the pressure drop in the pipe increases rapidly with the increase of thickness or decrease of permeability of the porous medium. So the porous medium should be partly filled in the practical application. The optimum filled thickness of porous medium is about 0.6 according to our model and analysis at which the heat transfer can be enhanced greatly while the pressure drop can be controlled in an acceptable range.