微细通道EHD两相流传热研究

以去离子水为工质,分别对1 mm×2 mm、2 mm×2 mm和3 mm×3 mm 3种矩形槽道进行了EHD两相流传热试验研究。结果表明,两相流饱和沸腾时,传热系数随着热流密度的增大而增大。在相同的热流密度下,槽道尺寸越小,槽道的饱和沸腾传热系数越大。在外加直流电压低于16 kV时,传热系数随外加电压的增加而明显增加;在16~20 kV之间,传热系数随电压的增加变得平缓;当电场电压高于20 kV后,传热系数随着电场强度的增加反而降低。这说明在EHD两相流强化传热中存在最佳强化电压。

Research on the heat transfer of the EHD two-phase flow in the micro-channel

Taking the deionized water as the working medium,an experimental study of the EHD two-phase flow heat transfer was conducted of the conduits with the dimensions of 1 mm× 2 mm,2 mm×2 mm and 3 mm×3 mm.The result showed that,when the two-phase flow saturated and boiled,the heat transfer coefficient increased with the increase of heat flow density.With the heat flow density remaining the same,the smaller the dimensions of conduits,the greater the saturation and boiling heat transfer coefficient of conduits would be.When the impressed DC voltage was lower than 16 kV,the heat transfer coefficient increased remarkably with the increase of impressed voltage.When it was between 16 and 20 kV,the coefficient became gentle with the increase of voltage.When the voltage of the electric field was higher than 20 kV,the coefficient decreased with the increase of the electric field's intensity.This indicated that there existed the optimal intensified voltage in the intensified heat transfer of the EHD two-phase flow.