With the rapid development of the aerospace field, traditional energy absorption materials are becoming more and more inadequate and cannot meet the requirements of having a light weight, high energy absorption efficiency, and high energy absorption density. Since existing studies have shown that carbon nanotube (CNT) buckypaper is a promising candidate for energy absorption, owing to its extremely high energy absorption efficiency and remarkable mass density of energy absorption, this study explores the application of buckypaper as the landing buffer material in a manned lunar lander. Firstly, coarse-grained molecular dynamics simulations were implemented to investigate the compression stress-strain relationships of buckypapers with different densities and the effect of the compression rate within the range of the landing velocity. Then, based on a self-designed manned lunar lander, buckypapers of appropriate densities were selected to be the energy absorption materials within the landing mechanisms of the lander. For comparison, suitable aluminum honeycomb materials, the most common energy absorption materials in lunar landers, were determined for the same landing mechanisms. Afterwards, the two soft-landing multibody dynamic models are established, respectively, and their soft-landing performances under three severe landing cases are analyzed, respectively. The results depicted that the landers, respectively, adopting the two energy absorption materials well, satisfy the soft-landing performance requirements in all the cases. It is worth mentioning that the lander employing the buckypaper is proved to demonstrate a better soft-landing performance, mainly reflected in reducing the mass of the energy absorption element by 8.14 kg and lowing the maximum center-of-mass overload of the lander by 0.54 g.

According to the randomness of the spatial distribution and shape of the internal cells of closed-cell foam aluminum and based on the Voronoi algorithm, we use ABAQUS to model the random polyhedrons of pore cells firstly. Then, the algorithm of generating aluminum foam with random pore size and random wall thickness is written by Python and Fortran, and the mesh model of random polyhedral particles and random wall thickness was established by the algorithm read in by TrueGrid software. Finally, the mesh model is impo rted into the LS-DYNA software to remove the random polyhedron part of the pore cell. Compared with the results of scanning electron microscopy and antiknock test, the morphology and properties of the model are close to those of the real aluminum foam material, and the coincidence degree is more than 91.4%. By means of numerical simulation, the mechanism of the wall deformation, destruction of closed-cell aluminum foams, and the rapid attenuation of explosion stress wave after the interference of reflection and transmission of bubbles were studied and revealed. It is found that aluminum foam deformation can be divided into four areas: collapse area, fracture area, plastic deformation area, and elastic deformation region. Therefore, the explosion resistance is directly related to the cell wall thickness and bubble size, and there is an optimal porosity rule for aluminum foam antiknock performance.

In this article, based on the real shape of gravel particles, a random polyhedron model is established, and a three-dimensional (3D) finite element (FE) analysis method is proposed to study the wave dissipation of broken gravel. In this article, the generation algorithm of 3D gravel with random size and shape is proposed, and the 3D meso-model of gravel particles is established. The numerical simulation of air explosion of explosive in free field is carried out by using LS-DYNA software, and the sensitivity of grid size was verified. Finally, it is concluded that the meshing calculation result of 0.01m element is more reliable. In order to verify the effectiveness of the analysis method, the numerical results are compared with the limited experimental data, and a good agreement is obtained, which shows that the 3D mesoscopic model and the numerical analysis method of gravel particle system can reliably predict the propagation of shock wave in gravel. Then, the wave dissipation performance of gravel layer under three working conditions of no water, partial water and all water is explored, and the dynamic response, energy analysis and meso-deformation of gravel particles are studied by numerical simulation. It is concluded that the gravel particle system significantly weakens the shock wave, and the peak pressure attenuates exponentially in the velocity direction, and the existence of water will affect the attenuation ability of the explosion wave.

In the article titled “Explosion Resistance of Three-Dimensional Mesoscopic Model of Complex Closed-Cell Aluminum Foam Sandwich Structure Based on Random Generation Algorithm” [1], there was an error in Figures 1(c) and 2 due to the incorrect version of the code being used. The authors confirm that this does not affect the results and conclusions of the article, and the corrected Figures 1(c) and 2 are as follows: