Explosion behaviors of IPN/air mixture at high temperature and high pressure

Purpose: The reaction dynamics of combustible clouds at high temperatures and pressures are a common form of energy output in aerospace and explosion accidents. The cloud explosion process is often affected by the external initial conditions. This study aims to numerically study the effects of airflow velocity, initial temperature and fuel concentration on the explosion behavior of isopropyl nitrate/air mixture in a semiconstrained combustor. Design/methodology/approach: The discrete-phase model was adopted to consider the interaction between the gas-phase and droplet particles. A wave model was applied to the droplet breakup. A finite rate/eddy dissipation model was used to simulate the explosion process of the fuel cloud. Findings: The peak pressure and temperature growth rate both decrease with the increasing initial temperature (1,000–2,200 K) of the combustor at a lower airflow velocity. The peak pressure increases with the increase of airflow velocity (50–100 m/s), whereas the peak temperature is not sensitive to the initial high temperature. The peak pressure of the two-phase explosion decreases with concentration (200–1,500 g/m³), whereas the peak temperature first increases and then decreases as the concentration increases. Practical implications: Chain explosion reactions often occur under high-temperature, high-pressure and turbulent conditions. This study aims to provide prevention and data support for a gas–liquid two-phase explosion. Originality/value: Sustained turbulence is realized by continuously injecting air and liquid fuel into a semiconfined high-temperature and high-pressure combustor to obtain the reaction dynamic parameters of a two-phase explosion.