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In this study, molecular dynamics (MD) simulations coupled with multi-scale shock technique (MSST) are used to predict the Hugoniot curve PH, Grüneisen coefficient γ and melting temperature Tm of single crystal (SC) and nanocrystalline (NC) aluminum (Al) with grain sizes of 6 and 60 nm at dynamic high pressure. The linear relation between the shock wave velocity and particle velocity is reproduced, and the results indicate that there is nearly no difference for the Hugoniot of SC and NC Al, which could be explained by the fact that the grain size effect on PH can be negligible at high pressure. Some empirical models are used to predict γ and Tm, which exhibit an opposite behavior. In addition, it is found that the melting pressure and temperature are 107.5 GPa, 3063 K for SC Al, while they are 109.5 GPa, 3082 K for NC Al, which have a reasonable agreement with the published work.

Summary Nowadays, metal hydrides are generally deemed as one of the most potential materials that are in favor of compact hydrogen storage for industrial applications. This work was committed to evaluate the thermal performance of a circular‐shaped‐tube thin double‐layered hydrogen storage reactor using a three‐dimensional model. Finite element simulations were conducted to systematically study the influences of structural geometries, cooling patterns, and material thermophysical properties on the heat diffusion behavior under the framework of convection heat transfer. The results indicate that the proposed model effectively characterizes temperature evolutions during hydrogen absorption process. Moreover, a statistical analysis was performed to reveal the sensitivity sequence of these factors on the total thermal performance, suggesting that decreasing the hydride layer thickness, increasing the number of U‐shaped cooling tubes, accelerating the cooling fluid flow rate, and enhancing the thermal conductivity are more beneficial to the thermal performance improvement. Detailed analysis confirms the possibility of developing the present hydrogen storage tank utilizing metal hydrides for engineering practice.

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