Experimental Investigation of Microwave-Assisted Kerosene Supersonic Combustion

Abstract

ABSTRACT The microwave-assisted kerosene combustion in supersonic flow was invested experimentally using a novel microwave-flame coupling method. The experiment used a direct-connected system, with a horn antenna employed to introduce microwaves into the combustion chamber, generating a traveling wave within the cavity. The microwave field simulation results confirm this coupling method’s feasibility. The experimental results showed that with the influence of the microwave, the flame’s stable position moved upstream by 7.4 mm. The average velocity of flame propagation increased by 64% upstream of entering the cavity and by 61% upon exiting it. The specific impulse of the scramjet was increased by about 4% under a 700W continuous microwave. In the presence of hydrogen, there was a significant increase in the excitation of NO and N2. However, in hydrogen-free combustion processes, the enhancement of radicals was considerably less compared to ignition processes, suggesting a close correlation between microwave-assisted combustion and hydrogen. These experimental results validate the feasibility of the microwave-combustion coupling method, representing a novel exploration into microwave-assisted kerosene combustion that aligns more closely with the practical application scenarios of scramjet engines.