Abstract: During the takeoff phase, aero-engines and their hydrodynamic seals are subjected to intense acceleration, leading to sudden changes in operating conditions that can easily cause seal instability, thereby limiting the application of large-scale engines. Investigating the impact of acceleration variations on seal stability is crucial for reducing leakage and mitigating rubbing of sealing rings. In this paper, a dynamic model was established to relate takeoff acceleration excitation to film thickness response and system leakage rate, effectively extracting key excitation parameters of take off acceleration. By numerically solving the Navier-Stokes equations, crucial parameters of the aero-engine end face seal were accurately obtained, including opening force, and fluid film stiffness, and so on. Based on this, the Volterra series theory was innovatively applied to calculate the frequency domain response of the fluid film induced by excitation, and the effects of excitation force, rotational speed, and pressure on leakage rate were systematically analyzed. The study revealed that when the main axis rotated at speeds between 1500~3000 r/min, rubbing occurred between the rotating and stationary rings, and as the rotational speed increased, the excitation frequency band for contact gradually narrowed. Under constant excitation frequency and force, the thickness of the fluid film and leakage rate increased with the rise in rotational speed and pressure. The theoretical calculation results were consistent with experimental data. This research deepened the understanding of the stability mechanism of aero-engine end face seals under sudden operating conditions and provided a theoretical foundation for related fields.