Research On The Characteristics Of Detonation Wave And Combustion Products In Annular-sector Detonation Tube

In order to improve the volume utilization and high performance of multitude pulse detonation engine, a sector cross-section tube was used. As the characteristic of detonation wave initiation and transmission in a sector cross-section is different from in circular cross-section tube, numerical study method of three-dimensional detonation in a sector cross-section tube is established to find out the characteristic of sector cross-section PED. The characteristic of detonation wave with different fuels and structures in suitable chemical mechanism was studied, the results show that, first, the progradation of detonation wave in sector cross-section tube is from the lower camber side to up camber side ,then stability in the center of sector cross-section tube, in short, in a heeling condition . Second, the annular-sector Structure play an important role in influencing detonation initiation and transmission, the optimal section structure with aspect ratio of 2.1,radians of 45 and external radius of 17.4 millimeters was obtained by simulating and analyzing multi sets of section parameters. Third, the optimum obstacle to accelerate the deflagration to detonation transition was designed by comparing with four different obstacle structures. Forth, the effect of radiation to the characteristic of detonation wave in single pulse was little, but the temperature distribution in detonation tube was distinct on account of the radiation heat transfer between the gas and wall. Fifth, the main oxid-nitride is NO and the main pollutant is CO and NO in the combustion product, whereas N2O is the main composition in the fresh mixture.The research results will provide steady theoretical and technical foundation for application of multitude pulse detonation engine.