微槽道内饱和沸腾传热试验及其动力学分析

以去离子水为工质,在高为2mm,宽分别为0.3,0.6,2mm的铝制矩形槽道内进行了饱和沸腾换热试验。试验结果表明,去离子水在微尺度条件下其换热特性优于常规尺寸。且随着槽道尺寸减小,其换热能力逐渐增强。最后对0.6mm×2mm的矩形微槽进行试验,获得了压差随时间波动图。对该序列进行Lyapunov指数计算,结果表明,系统出现了混沌,表明微尺度的传热性能与系统的混沌特征有一定的关系。

Experiment of saturated boiling heat transfer in microchannels and its dynamics study

The experiment of saturated boiling heat transfer was conducted with deionized water as working fluid in aluminum rectangular microchannels with the height of 2 mm,the width of 0.3,0.6 and 2 mm,respectively. The experimental results show that the heat transfer characteristic of deionized water in microchannel is superior to that of in conventional channel and more obvious when channel dimensions decrease. The experiment for the fluctuation chart of pressure drop with time was performed in the microchannel of 0.6 mm×2 mm. Lyapunov exponent calculation results indicate that chaos appears in this system,expressing the relationship between the heat transfer characteristic of microscale and the chaotic characteristic of the system.