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采用单步化学湿法(超声膜扩散法)制备出了3种体积分数的水基银纳米流体,实验研究了纳米流体横掠新型水滴形微针肋热沉的流动和传热特性.结果表明:不同体积分数下的纳米流体压降差别很小;相同体积流量下,与基液比较,纳米流体进出口压降略有增加,但增加并不明显;与纯水相比,由于表面活性剂的引入增加了流体粘度,相同流量下,纳米流体的压降稍大于纯水值,但最大差距不超过10%.粒子的体积份额对纳米流体对流换热系数影响较大.纳米粒子的存在对换热性能有明显提高,但过高的黏度对纳米流体的强化传热效果有一定的抑制作用.与去离子水相比,当银粒子体积分数达到0.012%后,纳米流体的综合效果才能逐渐体现.
Three kinds of water-based silver nanofluids with volume fraction were prepared by one-step chemical wet method (ultrasonic membrane diffusion method), and the flow and heat transfer characteristics of the novel droplet-shaped microneedle heat sink were experimentally studied. : The pressure drop of nanofluid under different volume fraction is very small. Compared with the base liquid, the pressure drop of nanofluid at the same volume flow slightly increases, but the increase is not obvious. Compared with pure water, , The pressure drop of nanofluids is slightly larger than that of pure water at the same flow rate, but the maximum difference does not exceed 10%. The volume fraction of particles has a great influence on the convective heat transfer coefficient of nanofluids. The heat transfer performance is obviously improved, but the too high viscosity has a certain inhibitory effect on the enhanced heat transfer effect of nanofluids.Compared with deionized water, when the silver particle volume fraction reaches 0.012%, the comprehensive effect of nanofluid can gradually reflect.