固体燃料冲压发动机工作过程数值模拟研究

【作者】 林小迪；

【导师】 武晓松；

【作者基本信息】 南京理工大学 ， 飞行器设计， 2011， 硕士

【摘要】 固体燃料冲压发动机(SFRJ)是一种吸气式发动机,具有结构简单,比冲高,高速飞行性能良好,可靠性好等优点。它具有广泛的应用前景,国内外做了很多的研究工作。本文以固体燃料冲压发动机为研究对象,采用理论分析和数值仿真相结合的方法,对固体燃料冲压发动机的工作过程进行计算分析研究。本文的研究内容包括以下两个部分：第一,针对某型60mm固体燃料冲压发动机的燃烧室,基于κ－ε湍流模型,多组分、多步反应机理模型以及EDC燃烧模型,建立了固体燃料冲压发动机燃烧室仿真模型并对该型发动机进行了数值仿真,分析了流动和燃烧特点,得到了燃速变化曲线。曲线与国外实验结果吻合较好,验证了该模型的正确性。将使用多步模型的计算结果同使用单步反应模型的计算结果进行了对比分析,结果表明,使用单步反应模型的燃烧室温度、压强均偏高,燃速也比使用多步反应模型的计算结果误差大。第二,针对某固体燃料冲压发动机的模型,基于κ－ε湍流模型,简单反应模型以及涡耗散燃烧模型,建立了固体燃料冲压发动机的统一内流场模型,对固冲统一内流场进行了数值仿真,分析了不同来流马赫数,燃烧室直径对固体燃料冲压发动机流场、再附点位置、燃速以及发动机性能参数的影响,结果显示随着燃烧室直径增大,再附点位置会后移,随着来流马赫数或燃烧室直径增大,燃烧室温度会升高,燃烧室内局部燃速也会增大。更多还原

【Abstract】 As a new air-breathing engine, the solid fuel ramjet (SFRJ) engine has many desirable advantages, including simple configuration, high specific impulse, well performance in high-speed flight and low cost. It has excellent application prospect and there are a lot of research on it both at home and abroad. Aiming at SFRJ, this dissertation explores computation and analysis research for the working process of SFRJ in the method of theoretical analysis combined with numerical simulation.The research of this dissertation can be divided into two parts:First, aiming at a 60mm SFRJ, based on standard two equation (κ-ε) turbulence model, multistep global reaction mechanisms and EDC combustion model, the simulation model for combustion chamber of solid fuel ramjet is established. Then, the characters of flow and combustion are analyzed and regression rate along the fuel grain is obtained. That the calculated results are in good agreement with the experimental data abroad confirms the correctness of the presented simulation methold. Besides, when compared with multi-step reaction, the temperature and pressure of combustion chamber simulated in one-step reaction have been found to be slightly higher and the relatively larger error of regression rate occurs.Second, aiming at a SFRJ assisted range projectile, based on standard two equation(κ-ε) turbulence model, simple reacting flow model, the whole internal flow field of SFRJ is established and the flow characters of the internal flow field, the location of reattachment point, the regression rate along the fuel grain and the performance parameters are investigated under varying Mach number and diameter of the combustion chamber. Results show that, the location of reattachment point shifts backward with increaing of diameter of the combustion chamber. Besides, the temperature and the regression rate along the fuel grain.rises in the combustion chamber as the diameter of the combustion chamber and flow Mach number increase.更多还原