化工进展2017，Vol.36Issue(5)：1649-1657,9.DOI:10.16085/j.issn.1000-6613.2017.05.013
微通道内浓度对纳米制冷剂流动沸腾压降波动的影响
Influence of nanoparticles concentrations on pressure drop fluctuation of nano-refrigerant flow boiling in microchannels
摘要
Abstract
Nano-refrigerants(0.1%—0.4%Al2O3/R141b) which used Span-80 as a dispersant were manufactured by ultrasonic vibration. They were used as working fluids to investigate the effect of nanoparticles concentrations on flow boiling pressure drop fluctuation under the designed conditions. An experiment on flow boiling of nano-refrigerant was conducted in rectangular microchannels with the hydraulic diameter of 1.33mm.The results showed that nanoparticles concentrations have significant impact on flow boiling pressure drop fluctuation of Al2O3/R141b. Under certain conditions, the average pressure drop of the 0.1%,0.2%,0.3%,0.4wt% nanofluids decreased by 9.4%,20.1%, 23.2% and 36%,respectively,than the pure refrigerant,The standard deviation of the pressure drop was reduced on average 8.0%,22.7%,28.6% and 33.9%,accordingly. That indicates that total pressure drop decreases and the fluctuation is more gradual with the increase of nanoparticles concentrations. Scanning electron microscopy(SEM)and measuring surface static contact angle revealed that the deposition of nanoparticles on the surface of microchannels is more pronounced and the surface static contact angle become smaller with the increase of concentration. It proves that the cause ofthe influence of nanoparticles concentrations on flow boiling pressure drop and fluctuation is nano-refrigerant with higher concentration deposits more,reducing the roughness of the wall surface but increasing the wettability of the wall surface.关键词
微通道/纳米粒子/浓度/压降波动Key words
microchannels/nanoparticles/concentrations/pressure drop fluctuation分类
能源科技引用本文复制引用
罗小平,郭峰,谢鸣宇,张霖..微通道内浓度对纳米制冷剂流动沸腾压降波动的影响[J].化工进展,2017,36(5):1649-1657,9.基金项目
国家自然科学基金项目(21276090). （21276090）
