Study on the influence of afterburning effect on implosion characteristics in different energy release rates

To examine the influence of afterburning energy load generated by explosive detonation products on the damage characteristics of confined space, a closed space model is constructed with steel plates. Additionally, the quasi-static pressure in the confined space is simplified by applying the law of conservation of energy.Relying on the adiabatic index of the mixture of detonation products and air as well as the complete afterburning degree of detonation products, a simulation method for the afterburning effect is proposed. This method is used to calculate the afterburning energy of detonation products and determine the beginning and ending times of the afterburning effect.The numerical simulation of implosion ruin in confined space is carried out by this method. The implosion simulation considering afterburning energy load is performed by employing two simulation methods: constant reaction rate and linearly increasing reaction rate.The results are compared with the implosion simulation results without considering the afterburning effect. The influence and degree of change of the afterburning effect on the implosion damage characteristics are analyzed. The analysis of the research results shows that by adding explosive energy, simulations of afterburning energy loads with different reaction rates are carried out. It is found that except for the temperature in the confined space, the numerical simulation of the afterburning effect with different reaction rates has a significant influence.Moreover, the enhancement effect of the constant reaction rate is the most significant. It increases the velocity and acceleration loads under implosion in confined space by 42.67% and 71.21% respectively. The overpressure and quasi-static pressure are increased by 63.68% and 74.95% respectively, and the kinetic energy is increased by approximately 212%.The implosion simulation is conducted by applying the afterburning effect with different reaction rates. It is found that the afterburning effect has a significant influence on the detonation damage characteristics within the confined space. The proposed simulation method for the afterburning effect can better simulate the dynamic response of implosion ruin in confined spaces and can provide a more accurate simulation method of the afterburning effect for the design and evaluation of explosion-proof structures.