Aiming at studying the influence of actuating frequency on plasma assisted detonation initiation by alteating current dielectric barrier discharge,a loosely coupled method is used to simulate the detonation initiation process of a hydrogenoxygen mixture in a detonation tube at different actuating frequencies.Both the discharge products and the detonation forming process which is assisted by the plasma are analyzed.It is found that the pattes of the temporal and spatial distributions of discharge products in one cycle are not changed by the actuating frequency.However,the concentration of every species decreases as the actuating frequency rises,and atom O is the most sensitive to this variation,which is related to the decrease of discharge power.With respect to the reaction flow of the detonation tube,the deflagration-to-detonation transition (DDT) time and distance both increase as the actuating frequency rises,but the degree of effect on DDT development during flow field evolution is erratic.Generally,the actuating frequency affects none of the amplitude value of the pressure,temperature,species concentration of the flow field,and the combustion degree within the reaction zone.