泡沫金属结构对池沸腾换热特性的影响

Effect of Metal Foam Structure on Pool Boiling Heat Transfer Characteristics

本文实验研究了制冷剂在不同结构泡沫金属表面的池沸腾换热特性。测试样件为泡沫铜,样件结构涵盖不同的孔密度(5~40 PPI)、孔隙率(0. 90、0. 95)与厚度(4~8 mm)。实验结果表明,孔密度为40 PPI泡沫金属比5 PPI泡沫金属最大表面传热系数提升了26. 4%;随着厚度增大,泡沫金属池沸腾换热先增强后减弱;孔隙率为0. 90泡沫金属比0. 95泡沫金属最大表面传热系数高13. 2%。根据实验结果,开发了制冷剂在不同结构泡沫金属表面池沸腾传热关联式,关联式与95%实验数据的误差在±30%以内,平均误差为12. 2%。

Pool boiling heat transfer characteristics of a refrigerant on heating surfaces of metal foams of different structures were experimentally studied.The test samples were copper foams of different pore densities(5–40 PPI),porosities(0.90 and0.95),and thicknesses(4–8 mm).The experimental results show that the maximum surface heat transfer coefficient of the metal foam increases by 26.4%as pore density increases from 5 to 40 PPI.The foam metal pool boiling heat transfer first increases and then decrease with an increase in thickness and the maximum surface heat transfer coefficient of the metal foam with a porosity of 0.90 is 13.2%larger than that with a porosity of 0.95.According to the experimental results,the boiling heat transfer correlation of the refrigerant on the surface with different structured metal foam is developed.The deviation between the prediction value of the correlation and 95%of the experimental data is within±30%and the average deviation is 12.2%.