《高超轴对称曲面压缩系统的初步研究》由会员分享，可在线阅读，更多相关《高超轴对称曲面压缩系统的初步研究（74页珍藏版）》请在金锄头文库上搜索。
1、南京航空航天大学 硕士学位论文 高超轴对称曲面压缩系统的初步研究 姓名：向有志 申请学位级别：硕士 专业：航空宇航推进理论与工程 指导教师：张堃元 2010-12 南京航空航天大学硕士学位论文 i 摘摘 要要 高超进气道压缩面的气动设计实际上是压缩面与波系二者的组织过程， 如何高效率地组织、 利用激波或者压缩波来对气流进行压缩是设计高超进气道的关键。本文研究了一种新型的轴对 称压缩曲面设计方法，它可以根据预先给定的沿程压升规律生成物理压缩面。设计中采用有旋 特征线理论并结合 Taylor-Maccoll（T-M）方程等按照给定的沿程压升规律逐步求解，最终得到 物理压缩面及流场结构。该压缩面为内
2、凹曲面，产生的激波为内凹弯曲激波，气流在经过曲激 波后还经受了等熵压缩波的压缩，气流的压缩除了第一道激波压缩外，还有相当大程度的等熵 压缩，故该流场具有较高的压缩效率。 研究了等压力梯度压缩规律设计的流场特性，结果表明：该流场为有旋流场，且离壁面不 同距离的流线上的压升规律、马赫数分布规律以及密度分布规律均不同，不同位置的流线亦无 相似性。 沿程压升规律直接确定了曲面的形状及性能， 因此有必要研究压升规律对曲面性能的影响。 曲面的压升规律多种多样，本文对曲面的压升规律进行分段设计，即分前段、中段及尾部进行 设计，每段的压力梯度均为线性分布，且保证整个曲面的压力分布连续可导，该压升规律的确 定需
3、要五个设计参数。针对该压升规律，研究了五个设计参数对曲面性能的影响规律，结果表 明：随着任何一个设计参数的增大，设计点曲面总压恢复系数下降、增压比增加、阻力系数增 加、总压缩角增大及长高比增大，其中 K2、K3 的影响占主导地位；此外，这种内凹弯曲激波对 来流马赫数不敏感。 基于设计参数对曲面性能的影响结果，建立了近似模型，并采用遗传算法对曲面进行了单 点多目标及多点多目标优化设计，并得到了一系列最优解集。基于优化结果设计了新型高超轴 对称进气道，对其进行了数值研究，并与常规三锥、锥加等熵轴对称进气道进行了比较。数值 计算结果表明：本文条件下，该设计方法能有效缩短进气道的长度，较三锥进气道及锥
4、+等熵进 气道分别缩短 11.8%、26.8%；在设计点其总压恢复系数与三锥进气道相当；在接力点其流量系 数比三锥、锥加等熵轴对称进气道分别提高 19.3%、24.2%，且对来流马赫数的变化不敏感； 其总压恢复系数比三锥及锥+等熵进气道分别提高 6.32%、4.99%；曲面轴对称进气道具有较好 的攻角特性，对攻角的变化不敏感。体现了该新型进气道优越的总体性能。 关键词：高超声速轴对称进气道；优化设计；弯曲激波；曲面 高超轴对称曲面压缩系统的初步研究 ii Abstract The aerodynamic design of compression surface in hypersonic i
5、nlet is essentially an organization of the wall and shock system, so the key problem is how to efficiently compress coming flow with shock waves or compression waves. This paper investigated a new method of designing axisymmetric compression surface, which can generate physical compression wall acco
6、rding given pressure distribution. In the designing, a step by step process developed from theory of rotational characteristics and Taylor-Maccoll（T-M）equation, is repeatedly applied according to the assigned pressure distribution, and ultimately the compression wall and the whole flow field can be
7、obtained. The compression wall, a concave surface, would generate a concave shock wave. The compression efficiency is higher, because the free stream can be compressed by both shock wave and, more isentropic compression waves. The flow characteristic of compression surface with constant pressure gra
8、dient was investigated. The result shows, the flow is rotational; along different streamlines, the pressure distribution, Mach number distribution and the density distribution is different; and similarity law can not be satisfied between different streamlines. The influence of the pressure distribut
9、ion on the compression performance was specially investigated, due to the importance of the pressure distribution to the shape and property of the compression surface. The pressure distribution rules can be various much, and this paper proposed a piecewise rule. The surface is divided into front, mi
10、ddle and rear segment, and each has linear pressure gradient distribution, in addition the entire pressure distribution function is kept continuous and derivative, then totally 5 independent parameters are needed. Under this pressure distribution rule, influence of the 5 designing parameters on the
11、compression surface performance was studied. The result indicates, under the designing condition, total pressure recovery of the surface decreases, while pressure ratio, drag coefficient, total compression angle and length-height ratio all increase with the increase of each parameter, of which K2 an
12、d K3 have most huge impact; and the flow are not very sensitive to the coming flow condition. Based on above results, a surrogate model was established, and then single-objective and multi-objective optimization were carried out using genetic algorithm, ultimately several Pareto set were obtained. A
13、 new hypersonic axisymmetric inlet was designed using one of 南京航空航天大学硕士学位论文 iii the optimal solutions. The new inlet was investigated through numerical simulation, and was compared with the normal triple-cone and cone-isentropic inlet. The numerical simulations indicated that, under the present cond
14、ition, the inlet length can be reduced remarkably, about 11.8% and 26.8% of the triple-cone and the cone-isentropic inlet respectively; under the design point, total pressure recovery of the new inlet is approximately the same as triple-cone inlet; under the start point the flow capture ratio is imp
15、roved by 19.3% and 24.2% than the triple-cone and cone-isentropic inlet respectively, and is not very sensitive to the change of coming flow Mach number; under the start point the total pressure recovery is improved by 6.32% and 4.99% than the triple-cone and cone-isentropic inlet respectively; the
16、new inlet has better performance at angle of attack than normal inlet, and is not very sensitive to the change of attack angle. Generally speaking, the new inlet has a superior overall performance. Key words: hypersonic axisymmetric inlet ;multi-objective optimization; curved shock; curved compression surface 南京航空航天大学硕士学位论文 vii 图表目录 插图清单 图 1.1 各类发动机的燃料比冲图.1 图 1.2 超燃冲压发动机结构示意图2 图 1.3 HRE 轴对称进气道 3 图 1.4 Hyfly 导弹用的模块化轴对称进气道3 图 1.5 俄印合作的 BrahMos .3 图 1.6 美国的 SR-71.3 图 1.7 Busemann 进气道 4 图 1.8 NASA L
