Experimental Research on Operational Characteristics of a Helmholtz-Type Valveless Self-Excited Pulse Combustor

This paper designed and described a Helmholtz-type valveless self-excited pulse combustor with continuous fuel and air supply. Its structure is similar to the conventional Helmholtz type's, but valves are not used. The operational characteristics of the Helmholtz-type valveless self-excited pulse combustor was investigated by the experiment. The effects of the excess air ratio, tailpipe length and heat load on the frequency and pressure oscillation were researched. The results show that the frequency decreases with the increase of excess air ratio and tailpipe length, and increases with the increase of heat load. The tailpipe length has a significant effect on frequency. The pressure amplitude increases with the increase of excess air ratio and heat load, and decreases slightly with the increase of tailpipe length. The excess air ratio has the greatest significant effect on pressure amplitude.