CAJ | 학술논문

超燃冲压发动机在高空工作时,以高温高速纯净空气作氧化剂使燃料燃烧.但在地面实验中,高温空气往往通过燃烧加热方式获得,会使空气中含有H_2O和CO_2等污染组分.本文用活塞流反应器进行动力学模拟,研究在不同初温、压强和燃气比的条件下,H_2O和CO_2污染组分对乙烯燃烧的温度、压强和点火延迟时间等特性的影响.模拟结果表明:乙烯在含有H_2O/CO_2污染物的空气中燃烧,相比纯净的空气而言,H_2O对乙烯的点火有一定的促进作用,而CO_2有一定的抑制作用;空气中含H_2O和CO_2污染物使乙烯燃烧的平衡温度和压强降低,在污染物浓度相同时,CO_2引起的下降幅度比H_2O的大.模拟结果能较好地解释现有的实验现象.
초연충압발동궤재고공공작시,이고온고속순정공기작양화제사연료연소.단재지면실험중,고온공기왕왕통과연소가열방식획득,회사공기중함유H_2O화CO_2등오염조분.본문용활새류반응기진행동역학모의,연구재불동초온、압강화연기비적조건하,H_2O화CO_2오염조분대을희연소적온도、압강화점화연지시간등특성적영향.모의결과표명:을희재함유H_2O/CO_2오염물적공기중연소,상비순정적공기이언,H_2O대을희적점화유일정적촉진작용,이CO_2유일정적억제작용;공기중함H_2O화CO_2오염물사을희연소적평형온도화압강강저,재오염물농도상동시,CO_2인기적하강폭도비H_2O적대.모의결과능교호지해석현유적실험현상.
Clean air at high temperature and velocity is used as the oxidant during fuel combustion in a hypersonic scramjet. In ground tests, however, the high-temperature air produced by combustion heating contains H_2O and CO_2 as contaminants. In this study, the influence of H_2O and CO_2 in air upon the equilibrium temperature and pressure, and the ignition delay time for ethylene combustion were investigated by a kinetics simulation method using a plug flow reactor. Different initial temperatures, pressures, and equivalence ratios were studied. We find that the presence of H_2O promotes combustion whereas CO_2 inhibits combustion. Both H_2O and CO_2 result in a decrease of the equilibrium temperature and pressure during ethylene combustion, and CO_2 has a comparatively larger influence than H_2O. The simulated result was used to interpret the experimental phenomena.