采用一种考虑热损失的光热转换计算模型，实验研究Ag纳米流体的光热转换特性。在传统工质水中加入纳米颗粒，使工质对光的吸收和散射特性得到强化，从而获得较好的光热转换特性。颗粒体积分数为2.5×10-6的Ag纳米流体获得最大的温升67.31℃，是基液水的1.8倍。但是，由于在计算光热转换效率时考虑了热损失，其光热转换效率是基液水的2.9倍。随着颗粒浓度的增大，颗粒的温升和光热转换效率逐渐增大，温升和光热转换效率的变化速率均逐渐较小。
A calculation model incorporating the heat loss is used to study the photothermal conversion characteristics of Ag nanofluids in this work. Adding nanoparticles to the traditional working fluid enhances the light absorption and scattering to obtain better photothermal conversion abilities. The Ag nanofluid with a particle volume fraction of 2.5×10-6 leads to the maximum temperature rise of 67.31℃, which is 1.8 times that of the base fluid. However, its photothermal conversion efficiency is 2.9 times that of the base liquid since the heat loss is taken into account in the calculation model. With the increase in particle concentration, the temperature rise and the photothermal conversion efficiency gradually increase, and the change rates of temperature rise and photothermal conversion efficiency become gradually small.
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