Numerical simulation of disperse process of fuel-air explosive based on the computational fluid dynamics

The formation process of fuel cloud is easily affected by the material properties of fuel mixture and the structural qualities of manufacture. The spread region of fuel cloud plays an important role in the damage performance of FAE bomb. However, there are not sufficient simulation study on the disperse process, lacking a useful model for calculating the fuel cloud size due to the physical complexity in disperse process. In this work, a FAE bomb was designated at first and an experiment was carried out to measure the fuel cloud diameters. And then a computational model was established to illustrate the formation process of fuel cloud. This computational model consisted of an explosion dynamics model in the near-field stage and a fluid dynamics model in the far-field stage. Furthermore, multiphase turbulence flow, discrete phase and species chemical transportation were incorporated in the fluid dynamics model. The results showed that good agreements were yielded by comparison of the simulation results and experimental data for the fuel cloud diameters. The fuel cloud diameter at 220 ms was 9.11 m for simulation and 9.37 m for experiment. Additionally, it was also discussed the influence of particle size distribution on the formation process of fuel cloud. Larger particles were more likely to aggregate at the outside region of fuel cloud due to individual inertial influence. This study can provide an effective computation model for evaluation of the fuel cloud region, which can be worthwhile in understanding the physical mechanism of disperse process. image