氨水-Fe_2O_3纳米流体稳定性影响因素分析  

Dispersing of Fe_2O_3 Nano-Particles in Ammonia-Water Suspension

作　　者：杨柳[1] 杜垲[1] 李彦军[1] 程波[1] 

机构地区：[1]东南大学能源与环境学院,江苏南京210096

出　　处：《工程热物理学报》2011年第9期1457-1460,共4页Journal of Engineering Thermophysics

基　　金：国家自然科学基金资助项目(No.50876020)

摘　　要：为了将纳米颗粒的强化传热传质作用应用于氨水吸收制冷中,提出了在氨水溶液中添加Fe_2O_3纳米颗粒和表面活性剂十二烷基苯磺酸纳(SDBS)的纳米流体的配制方法,并通过沉降试验和吸光度测试方法对其稳定性进行了实验研究。研究了活性剂质量分数、超声分散时间和氨水浓度对稳定性的影响,确定了Fe_2O_(3-)氨水纳米流体分散的最佳工艺为:SDBS质量分数为0.8%,超声时间为30min,基液为25%的氨水。最后根据双电层原理分析了活性剂质量分数对悬浮液的稳定性的影响。结果表明在悬浮液的稳定性条件下,活性剂存在最佳质量分数,此结论与实验结果一致。In this paper, the dispersion stability of Fe2O3 nano-particles in ammonia water was investigated using the sedimentation and the light transmission ratio index methods with different concentration of surfactant, different durations of ultrasonic vibration and different concentrations of ammonia-water basefluid in order to apply nanofluid to the absorption system. Sodium dodecyl benzene sulfonate （SDBS） is used as the surfactants. The results show that the stability of nanofluid was exacerbated firstly, then was improved, and then was exacerbated again with the increase of concentrations of the ionic surfactants. The optimal dispersing condition was 0.8% of SDBS in 25% ammonia water base fluid with 30 minutes of ultrasonic vibration. Finally, based on electric double layer theory, the influence of concentration of surfactant on the stability of nanofluid was analyzed. The reaction of anionic surfactants to the Fe2O3 nano-particles and the existence of the optimal surfactant concentration were explained in accordance with the experimental results.

关 键 词：纳米Fe2O3 稳定性 表面活性剂 氨水 

分 类 号：TB611[一般工业技术—制冷工程]