MOLECULAR DYNAMICS STUDY ON THERMOPHYSICAL PROPERTIES OF Li2CO3/Na2CO3/K2CO3 AND THEIR MIXED MOLTEN SALT FOR HEAT STORAGE

Yang Xueming; Tao Jiawei; Meng Fanxing; Li Chunbo

doi:10.19912/j.0254-0096.tynxb.2022-0019

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Acta Energiae Solaris Sinica ›› 2023, Vol. 44 ›› Issue (5) : 48-58. DOI: 10.19912/j.0254-0096.tynxb.2022-0019

MOLECULAR DYNAMICS STUDY ON THERMOPHYSICAL PROPERTIES OF Li₂CO₃/Na₂CO₃/K₂CO₃ AND THEIR MIXED MOLTEN SALT FOR HEAT STORAGE

Yang Xueming, Tao Jiawei, Meng Fanxing, Li Chunbo

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Abstract

Molecular dynamics （MD） simulations of density, specific heat capacity, viscosity and thermal conductivity of Li₂CO₃/Na₂CO₃/K₂CO₃ and its binary and ternary mixed molten salts were carried out and compared with the experimental results. The simulation results are in good agreement with the existing experimental data and simulation values. The results show that with the increasing of temperature, the density decreases and the distance between ions increases, which lead to the decrease of resistance to shear stress, indicating the negative temperature dependence of viscosity of the single-component, binary and ternary molten salts. For the thermal conductivity of molten salt, the single-component and the binary molten salt also show a negative temperature dependence, while the ternary molten salt tends to increase with the increase of temperature.

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solar thermal power generation / carbonate / molecular dynamics / molten salt / specific heat / viscosity / thermal conductivity

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Yang Xueming, Tao Jiawei, Meng Fanxing, Li Chunbo. MOLECULAR DYNAMICS STUDY ON THERMOPHYSICAL PROPERTIES OF Li₂CO₃/Na₂CO₃/K₂CO₃ AND THEIR MIXED MOLTEN SALT FOR HEAT STORAGE[J]. Acta Energiae Solaris Sinica. 2023, 44(5): 48-58 https://doi.org/10.19912/j.0254-0096.tynxb.2022-0019

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