Zhu Chuang, Xu Minhao, Tian Baiyuan, Gu Manting, Gong Li
School of Energy and Electrical Engineering, Qinghai University, Xining 810016, China.
Engineer School, Qinghai Institute of Technology, Xining 810016, China.
Materials (Basel). 2024 Sep 20;17(18):4611. doi: 10.3390/ma17184611.
The aim of this study is to further enhance the thermal storage and heat transfer performances of a low-melting-point quinary salt. The eutectic salt was prepared using LiNO, NaNO, KNO, NaNO, and KNO as raw materials, followed by the doping of nano-SiO and nano-MgO into the base salt using a microwave-assisted method. The thermal properties of the samples were analyzed using a Synchronous Thermal Analyzer and a Laser Flash Apparatus. The co-doping of two types of nanoparticles was found to significantly enhance the specific heat capacity of the base salt. The maximum specific heat reached 2.36 J/(g·K), showing a 50.4% increase compared to the base salt. The thermal conductivity of molten salts can be affected by nanoparticles. An observed sample demonstrated a thermal diffusivity of 0.286 mm/s, indicating a 19.2% improvement over the base salt, which may be attributed to enhanced phonon thermal efficiency. In addition, this study revealed that while interfacial thermal resistance can enhance specific heat capacity, it can also lead to a decrease in the thermal conductivity efficiency of materials. This work can offer insights and references for the enhancement of molten salt properties.
本研究的目的是进一步提高低熔点五元盐的蓄热和传热性能。以LiNO、NaNO、KNO、NaNO和KNO为原料制备共晶盐，然后采用微波辅助法将纳米SiO和纳米MgO掺杂到基础盐中。使用同步热分析仪和激光闪光仪对样品的热性能进行了分析。发现两种类型纳米颗粒的共掺杂显著提高了基础盐的比热容。最大比热容达到2.36 J/(g·K)，与基础盐相比提高了50.4%。熔盐的热导率会受到纳米颗粒的影响。观察到的一个样品的热扩散率为0.286 mm/s，表明比基础盐提高了19.2%，这可能归因于声子热效率的提高。此外，本研究表明，虽然界面热阻可以提高比热容，但也可能导致材料热导率效率的降低。这项工作可为熔盐性能的提升提供见解和参考。
