【作者】 马立坤；

【导师】 夏智勋； 胡建新；

【作者基本信息】 国防科学技术大学 ， 航空宇航科学与技术， 2011， 硕士

【摘要】 新一代导弹对高性能动力装置的需求促进了燃气流量可调固体火箭冲压发动机(流量可调固冲发动机)的发展,但目前的研究成果尚不足以帮助人们清晰理解流量可调固冲发动机的工作过程,尤其是燃气流量调节中的参数动态响应过程,仍需进一步深入研究。本文主要通过理论分析和数值模拟的方法对流量可调固冲发动机的动态响应过程进行研究。通过理论分析,确定了流量可调固冲发动机流量调节过程中的负调现象的物理机理,从理论上回答了负调为何发生、何时发生、何时终止以及受何因素影响等问题,建立了负调理论。提出并定义了燃气流量调节临界喷喉面积变化率的概念。给出了临界喷喉面积变化率、负调持续时间、负调量和参数响应时间的理论计算方法。编程计算了不同喷喉面积变化速率的调节过程,计算结果验证了负调理论。燃气流量调节试验样机的试验结果也表明了本文负调理论相关内容的正确性。基于ALE描述的包含多组分化学反应的N-S方程,通过在成熟软件上的二次开发建立了流量可调固冲发动机动态响应过程数值模拟方法,该方法的正确性得到了一维稀疏波传播问题解析解和燃气流量调节试验结果的验证。开展了机械阀门式流量可调固冲发动机非稳态工作过程的数值模拟。计算了典型调节过程,分析了调节过程中发动机内部的流场结构变化和参数的动态响应情况。建立了流量可调固冲发动机动态响应过程评价体系,以该评价体系为指导计算并分析了阀门作动速度、阀门作动形式、推进剂燃速压强指数、调节尺度和燃气发生器自由容积对动态响应过程的影响。相关计算结果进一步验证了本文的负调理论。建立了气动喉道式流量可调固冲发动机的数值模拟方法,利用相关文献的试验结果验证了该方法的正确性。利用该方法开展了气动喉道式流量可调固冲发动机数值模拟研究,分别研究了其稳态调节特性和动态调节特性。计算结果表明,气动喉道确实可以达到改变燃气发生器喷喉面积进而调节燃气流量的目的,但是调节能力有限。分别计算并分析了二次流/主流流量比和二次流喷射角度对稳态调节特性和动态调节特性的影响,得到了相关结论,并证明了本文建立的负调理论对气动喉道式燃气流量可固体火箭冲压发动机也是适用的。更多还原

【Abstract】 Demonds for high performance propulsion system for the next generation missile have greatly promoted the research and development of Variable Flow Ducted Rocket (VFDR). Alough considerable progress in this field has been seen, still many issues, especially the response characteristics of VFDR, remained for us to conduct further investigation. Approaches of theoretical analysis and numerical simulation were both applied to study the response characteristics of VFDR in this dissertation.Physical mechanisms of anti-regulation phenomenon in the regulation process of VFDR have been discovered through theoretical analysis. A theory of anti-regulation was established, and it theoretically answered the questions of why does anti-regulation happen, when does it happen, when will it stop and how is it influenced by some given parameters. The concept of Critical Change Rate of gas generator Throat Area (CCRTA) were initiated and defined, calculation methods of CCRTA, anti-regulation duration and anti-regulation extent were also provided. The anti-regulation theory was validated by theoretical calculation results and VFDR experiment data.Based on ALE depicted N-S equations as well as dynamic mesh method, an unsteady numerical simulation method for the unsteady working process of VFDR has been established. The correctness of this simulation method was verified by analytical solution of one dimensional expansion wave propagation problem and VFDR experiment data.Numerical investigation of the unsteady working process of mechanical valve style VFDR was conducted, the variation of flow field inside the VFDR and the response characteristics were analyzed. An evaluation system of the response characteristics has been established. The influences of valve velocity, pressure exponent, free volume etc. were calculated and analyzed. The anti-regulation theory was validated again.Numerical simulation method of gas throat style VFDR was established and validated by relevant experiment data. Steady and Unsteady regulation property of gas throat style VFDR was studied using this method. The results demonstrated the feasibility of gas throat style VFDR. The influences of the secondary flow - main flow rate and secondary flow inject angle were investigated, which indicated that the anti-regulation theory established in this dissertation is also suitable for gas throat style VFDR.更多还原