MOLECULAR DYNAMICS SIMULATION RESEARCH OF THERMOPHYSICAL PROPERTIES OF CHLORIDE MOLTEN SALTS AND THEIR MIXTURES

Yang Xueming; Liu Jieting; Cui Jixiang; Zhang Mingli; Meng Fanxing

doi:10.19912/j.0254-0096.tynxb.2021-0525

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Acta Energiae Solaris Sinica ›› 2022, Vol. 43 ›› Issue (11) : 433-442. DOI: 10.19912/j.0254-0096.tynxb.2021-0525

MOLECULAR DYNAMICS SIMULATION RESEARCH OF THERMOPHYSICAL PROPERTIES OF CHLORIDE MOLTEN SALTS AND THEIR MIXTURES

Yang Xueming¹, Liu Jieting¹, Cui Jixiang², Zhang Mingli¹, Meng Fanxing¹

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Abstract

Comprehensive molecular dynamic simulations were carried out to compute the thermophysical properties of three commonly used chloride molten salts and their binary and ternary mixtures over a wide operating temperature range. The viscosities were calculated by the equilibrium molecular dynamics （EMD） method, and the thermal conductivities were calculated by the non-equilibrium molecular dynamics method. Compared with the experimental data, the absolute relative errors of the simulation results of the specific heat capacities for the three kinds of chloride molten salts are all within 6.8%. The simulated viscosities differ from the experimental data by 5.3%, 10.9%, and 11.7% for NaCl, KCl and LiCl, respectively. Except for LiCl, the averaged absolute relative errors of thermal conductivity for NaCl and KCl compared to the experimental data are less than 9%. Compared with the previous EMD study results, the absolute relative deviations of the thermal conductivities of the binary mixed KCl-NaCl chloride salts are within 12.5%. The results showed that the simulation results are in good agreement with the experimental values. To better understand the thermophysical properties of chloride molten salt at a molecular level, the partial radial distribution functions were calculated and local structures were analyzed.

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CSP / molten salt / molecular dynamics / specific heat capacity / viscosity / thermal conductivity

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Yang Xueming, Liu Jieting, Cui Jixiang, Zhang Mingli, Meng Fanxing. MOLECULAR DYNAMICS SIMULATION RESEARCH OF THERMOPHYSICAL PROPERTIES OF CHLORIDE MOLTEN SALTS AND THEIR MIXTURES[J]. Acta Energiae Solaris Sinica. 2022, 43(11): 433-442 https://doi.org/10.19912/j.0254-0096.tynxb.2021-0525

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