In this paper, a two-dimensional model of horizontal pipeline with built-in electric heat tracing device is established to simulate the position, shape and temperature field distribution of solid-liquid interface of mixed molten salt nanofluid during the melting process, and to analyze the influence of different Ste and the size of the electric heat tracing device on the whole molten salt melting process. The results indicate that, as the heating duration increases, the distance between the electric heating system and the phase interface increases, and the transfer of heat to the molten salt in the solid phase gradually slows down due to the increase in thermal resistance. and the molten salt nanofluid is completely melted when the heating time lasts for 3082 s. The temperature of the solid-liquid interface is reduced by the influence of the thermal resistance of the electric trace heating device. When Ste increases from 0.392 to 0.706 and 1.021, the complete melting time of the molten salt nanofluid is reduced by 66% and 81%, respectively; compared with the 5 mm diameter electric trace heating device, the melting efficiency of the molten salt of the electric trace heating device with diameters of 10 mm and 20 mm is increased by 68% and 82%, and the time of complete melting of the molten salt is 1100 s and 623 s, respectively.

solar thermal power generation  /  heat transfer  /  phase change  /  melt  /  nanofluids  /  molten salt  /  electric heating element