At present, concentration of explosive dispersal is very difficult and uncertain to measure. Numerical experimentation can avoid this deficiency. Data of particles during dispersal are readily available, including velocity, displacement, and mass. However, there is minimal research on the concentration of explosive dispersal. Existing models used for the calculation of particle concentration neglect measuring the initial condition of particles and cannot, therefore, accurately describe the whole particle dispersion process. Moreover, existing concentration models do not take into account the continuous decrease in the size of particles caused by stripping and evaporation effects during flight, resulting in inaccurate descriptions of the concentration distribution. Consequently, this work derives a model to predict the concentration distribution of liquid and granular material dispersal, considering the two questions above. Concentration can be calculated based on the condensed-phase distribution and gas-phase distribution of the fuel cloud at different times by the model. This model was validated using experimental data on the mean concentration of dispersal and was well fitted. Therefore, it can be used as a tool to predict the dispersal of liquid and granular material, an explosion suppressant in coal mine accidents, and an aerosol fire extinguishant in remote forest fire extinguishers. Moreover, being able to predict the concentration of large-scale dispersal can significantly improve the accuracy and efficiency of secondary detonation.

The surrounding rock is divided into the elastic zone and the plastic zone according to the motion and deformation characteristics of the medium in rock blasting. The vibration caused by the cylindrical charge blasting is outlined on the basis of previous research concerning the blasting elastic-plastic theory. Meanwhile, a superposition model is used to calculate the vibration of cylindrical charge blasting on the premise of considering the influence of detonation velocity, the number of drug columns, and the time delay between holes. The analysis results show that the blasting causes the uneven spatial distribution of vibration, containing both strong and weak directions. The velocity of the vibration along weak directions decreases slowly with the increase of distance. But generally, the velocity along weak directions is faster. The vibration distribution of a cylindrical charge is closely related to the detonator location. Furthermore, more vibration distributes towards the forward direction of the detonation wave.

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