Ag纳米流体浸没射流冲击换热特性

Heat transfer of sub-merged jet impingement on pin-fin heat sinks with silver nanofluid

采用超声膜扩散法一步制备出水基Ag纳米流体作为实验工质,并对不同质量分数的Ag纳米流体在受限浸没阵列射流冲击针肋热沉中的流动和换热特性进行了实验研究。结果表明:采用超声膜扩散法制备的Ag纳米颗粒粒径分布均匀,平均粒径只有4.8 nm;表面活性剂对纳米流体的黏度影响较大;相同射流速度下,与基液(水+表面活性剂)相比,Ag粒子质量分数分别为0.02%、0.08%、0.12%的纳米流体传热系数分别提高6.23%、9.24%、17.53%;与纯水相比,Ag粒子质量分数为0.12%时,纳米流体传热系数增加6.61%。

Silver-water nanofluid,used as the working fluid in this study,was prepared in one step employing ultrasound-assisted membrane reaction.The heat transfer of submerged jet impacting pin-fin heat sinks was investigated experimentally with silver nanofluid of different concentrations.The results indicate that the silver nanoparticles prepared are uniformly distributed in base fluid and with an average grain size of 4.8 nm.The surfactant used in this study has great influence on the viscosity of nanofluids.Compared with the base fluid（water and surfactant）,the heat transfer coefficient of nanofluids is increased by 6.23%,9.24% and 17.53%,respectively,with the silver nanoparticle mass fraction of 0.02%,0.08% and 0.12%,under the same jet velocity.Compared with water,the heat transfer coefficient is enhanced by 6.61% with the silver nanoparticle of 0.12%.