Investigation of reactive fluid flow characteristics of high-energy propellants under periodic laser disturbance

During various missions involving solid rocket motors (SRMs), combustion instability poses a significant challenge, often leading to dangerous outcomes. To elucidate its mechanisms and enhance SRM design, this study investigates the reactive flow characteristics of non-aluminum NEPE propellants under periodic laser disturbances using a microscale model. The model integrates temperature-dependent condensed phase kinetics and gas-phase multi-flame interactions, revealing that surface morphology critically shapes gas product distributions near the surface, contributing to instability. Quantitative results demonstrate transient burning rate variations under different pressures (5–12 MPa) and laser powers (10–75 MW), with a maximum deviation of 5.67 % between simulations and experimental data. At 5 MPa, laser disturbance increases the transient burning rate by 20–35 % during energy application, while higher pressures (12 MPa) reduce thermal adjustment times by 40 % compared to lower pressures. Additionally, a critical laser power range (50–75 MW) significantly prolongs thermal stabilization durations. These findings provide insights into reactive flow dynamics under laser interference, supporting optimized propellant formulation and SRM design.