Modeling the effects of pressure and magnetic field on the phase change of sodium sulfate/magnesium chloride hexahydrate in nanochannels

Abstract

This work examines the impact of different pressure levels (1 to 5 bar) and magnetic field frequencies (0.01 to 0.05 ps⁻¹) on the thermal behavior of sodium sulfate/magnesium chloride hexahydrate as a phase change material inside iron nanochannels, using molecular dynamics simulation. The system's kinetic and potential energies converge to 39.79 eV and -7204.99 eV, indicating the stability of the nanostructures. The impact of pressure and magnetic field frequency on heat flow, maximum temperature, and charge/discharge times was examined. Increasing the pressure from 1 to 5 bar reduced the heat flux and maximum temperature to 1509 W/m² and 391.18 K, respectively. Simultaneously, the charge duration extendes to 3.99 ns, whilst the discharge duration decreases to 4.30 ns. Moreover, increasing the magnetic field frequency from 0.01 to 0.05 ps⁻¹ results in a decrease in maximum temperature and heat flux, which fell to 415.67 K and 1566 W/m², respectively. The charge time decreases to 3.87 ns and the discharge time to 4.50 ns little owing to the increase in frequency.