Experiments were conducted to study the combustion performance of ramjet engine model with trapped-vortex combustor under different inlet temperatures and velocity coefficients. The results show: with the increase of inlet velocity coefficient increases (0.20-0.35)

the ignition and lean blowout fuel air ratios rise

and the combustion efficiency changes little. As the inlet temperature increases(573-773K)

the ignition fuel air ratio and lean blowout fuel air ratio decreases

and the combustion efficiency increases varying with increase of the excess air coefficient(1.1-2.1). The minimum ignition fuel air ratio and the lean blowout fuel air ratio is 0.0035 and 0.0028 respectively

the maximum combustion efficiency obtained from experiment is 93%.The results prove the feasibility of applying the cavity to the ramjet combustor.