【作者】 周玲；

【导师】 李润华；

【作者基本信息】 华南理工大学 ， 光学， 2016， 硕士

【摘要】 油基纳米流体由于能够获得较高的流体温度,与水基纳米流体相比具有更大的应用价值。本文以氙灯、二氧化碳激光器作为辐照光源,结合超声搅拌的方法,制备了以透明导热油为基底的不同浓度的碳系列(C₆₀、石墨、炭黑)和金属化合物系列（CuO、HgS）的纳米流体,通过用分光光度计观察吸收谱及测量其在不同光源辐照下的温升变化情况,比较了几种纳米流体的光谱吸收特性和光热转换性能。结果表明在透明油中添加纳米粒子,显著强化了对辐照光的吸收,显示出很好的光热转换性能,且在一定浓度范围内,纳米流体的温升随着浓度增加而增大,随着浓度继续增大,因出现表面效应反而降低,实验数据显示可实现光热转化效率最大化的最佳浓度配比范围为0.1mg/ml-0.2mg/ml。分析表明:对于不同纳米流体而言,光热转换效率的提高分别是由于纳米颗粒的吸收和散射两种效应所导致的。实验还对同种浓度下不同种类的纳米流体进行光热转换测试以及不同种类、不同浓度纳米颗粒进行掺杂混合,结果表明不同纳米流体改善光热转换效率的途径有所不同,两种混合的纳米流体将表现出比单一纳米流体更好的光热转换特性。更多还原

【Abstract】 In comparing with water-based nanofluids, Oil-based nanofluids have more applicational value due to its high fluid temperature. Combined with ultrasonic stirring methods, we prepare different concentrations of carbon series(C60, graphite, carbon black) and a series of metal compounds(CuO, HgS) based on the transparent heat conducting oil. The radiation source such as xenon lamp and carbon dioxide laser are used. By using spectrophotometer, we observe absorption spectrum and measure their temperature change under different light irradiation. The photothermal conversion properties and absorption properties of different kinds of nanofluids are compared. Results show that fluids with nanoparticles added in can increase the absorption of light irradiation and show excellent photothermal conversion performance. In the certain concentration range, the rise of temperature of the nanofluids increases when concentration increases. But it reduce instead when the concentration continue to increase because of surface effect. The experimental data shows that the field range of optimal concentration ratio which can maximize photothermal conversion efficiency is 0.1mg/ml-0.2mg/ml. Analysis show that the improvement of conversion efficiency was major contributed by absorption effect and the scattering effect respectively for different nanofluids.Photothermal conversion experimental tests are also done about different nanofluids with the same concentration and mix nanoparticles of different types and different concentrations. Results show that different nanofluids have different ways to improve photothermal conversion efficiency and the two kinds of hybrid nanofluids will show better thermal properties than a single one.更多还原