Study on theoretical calculation of quasi-static pressure for aluminized explosive in confined space

The process of the explosion damage in confined space mainly involves two parts, shock wave pressure effect and quasi-static pressure effect. A complicated afterburning reaction occurs in the internal explosion of aluminized explosives, not only enhancing the intensity of the shock wave, but also having a great influence on the final quasi-static pressure. A theoretical calculation model of final quasi-static pressure for aluminized explosive in confined space considering afterburning effect was proposed, based on the analysis of chemical reaction, the law of conservation of energy and the improved Jones-Wilkins-Lee equation of state. The factor that the volume of gaseous explosive products decreases in the afterburning reaction was also taken into consideration. The results of RDX-based and HMX-based charges calculated by the model were then analyzed and compared with the references’ experimental results as well as Anderson’s empirical formulas’ to verify the reliability and correctness of the proposed model. The results show that: the final quasi-static pressure of aluminized explosive calculated by the theoretical calculation model is in good agreement with the results of experimental measurement in the papers and the relative error doesn’t exceed 10%; the Anderson’s empirical formula is inapplicable to predict the final quasi-static pressure of the aluminized explosive in confined space. The study in this paper can provide a better theoretical calculation model to predict the final quasi-static pressure of aluminized explosives and provide some reference and guidance for the assessment of internal explosion damage of aluminized explosive and the design of explosive-resistant structures.