2021-08期封面

铝粉反应模型是对悬浮铝粉尘气-固两相爆轰进行数值模拟研究的关键。通过考虑铝粉燃烧产物氧化铝（Al₂O₃）在高温下的分解吸热反应，改进了铝粉的扩散燃烧模型。将该模型嵌入到三维的气-固两相爆轰数值计算程序中，分别对铝粉/空气混合物以及铝粉/氧气混合物的爆轰进行了数值模拟，计算得到的稳定爆轰波速度与实验结果、文献值均吻合较好，误差小于5.5%，表明改进的铝粉反应模型适用于不同氧化气体氛围中铝粉尘爆轰的模拟计算。此外，对两相爆轰参数及爆轰流场的物理量分布进行分析，获得了铝粉反应模型对爆轰波结构的影响规律。

A modified reaction model of aluminum dust detonation

The reaction model of aluminum particles is the key to successfully simulate the two-phase detonation of aluminum suspensions. In this study, by considering the endothermic decomposition reaction of the aluminum oxide (Al₂O₃) product at high temperature, a diffusion combustion model for the aluminum particles was improved and was incorporated into the homemade numerical code for 3D simulation of gas-solid two-phase detonation. The numerical program is based on the theory of two-phase flows, both gaseous and solid phases are assumed to be continuous media with inter-phase transfer of mass, momentum and energy. The system of 3D governing equations is solved in Cartesian x-y-z coordinates using an Eulerian grid, the numerical simulation code uses an explicit finite difference scheme based on the space-time conservation element and solution element (CE/SE) method, and the fourth order Runge-Kutta method is used to solve the source terms of the governing equations. In addition, the stability is assured by the Courant-Friedrichs-Lewy (CFL) criterion. Program parallelization is realized based on the message-passing-interface (MPI) technique, and the reliability of the program is demonstrated by simulating the shock tube problem successfully. Based on the program and the improved reaction model for the aluminum particles, numerical simulations for detonations of Al/air mixtures and Al/O₂ mixtures were performed, respectively, the simulated results of the steady detonation wave speeds are in agreement with the experimental results or the literature value, with the error of less than 5.5%, which demonstrate the validity of the improved reaction model for Al suspensions detonation in different oxidizing atmosphere. Moreover, the detonation parameters and the distributions of the physical quantities around the detonation wave are analyzed, and the influence law of the reaction model on the detonation wave structure is obtained.