6.1飞机总体参数的多学科设计优化 6.1.1多学科设计优化的基本概念 飞机总体设计是一个复杂的系统工程,覆盖了多个学科的内容 ,例如空气动力学、结构学,推进理论,控制论等。 多学科设计优化是一种解决大型复杂工程系统设计过程中耦合 与权衡问题,同时对整个工程进行综合优化设计的有效方法

AMCM2001问题-A:选择自行车车轮 有不同类型的车轮可以让自行车手们用在自己的自行车上。两种基本的车轮类 型是分别用金属辐条和实体圆盘组装而成(见图1)辐条车轮较轻,但实体车 轮更符合空气动力学原理。对于一场公路竞赛,实体车轮从来不会用作自行车 的前轮但可以用作后轮

观察超音速下飞行器的升力、阻力的产生及绕飞行器流动的流场细节,包括激波、膨胀波的构型,可以采用以下两种方法: (1) Conduct flight tests using the actual vehicle 进行实际飞行器的飞行试验 (2) Run wind-tunnel tests on a small-scale modelof the vehicle 用飞行器的缩小模型进行风洞实验

All real substances are compressible to some greater or lesser extend. When you squeeze or press on them, their density will change. This is particularly true of gases. (所有的真实物质都是可压缩的,当我们压挤 它们时,它们的密度会发生变化对于气体尤 其是这样)

第八章我们讨论了正激波,本章我们讨论斜激波,及超音速流场中的另一个重要特征——膨胀波

Chapter 3 Fundamentals of Inviscid, incompressible Flow Theoretical fluid dynamics, being a difficult subject, is for convenience, commonly divided into two branches, one treating frictionless or perfect fluids, the other treating of viscous or imperfect fluids. The frictionles fluid has no existence in nature, but is hypothesized by mathematicians in order to facilitate the investigation of important laws and principles that may be approximately true of viscous or natural fluids

Chapter 1 Aerodynamics: Some Introductory Thoughts The term \aerodynamics\is generally used for problems arising from flight and other topics involving the flow of air. Ludwig Prandtl, 1949 Aerodynamics: The dynamics of gases, especially of atmospheric interactions with moving objects. The American Heritage Dictionary of English Language, 1969

Chapter 2 Aerodynamics: Some Fundamental Principles and Equations There is so great a difference between a fluid and a collection of solid particles that the laws of pressure and of equilibrium of fluids are very different from the laws of the pressure and equilibrium of solids Jean Le Rond d' Alembert, 1768

5.1 Introduction The properties of airfoils are the same as the properties of a wing with infinite span. However, all real airplanes have wings of finite span. In the present chapter, we will apply our knowledge of airfoil properties to the analysis for finite wings. As we have mentioned in the previous chapter, the analysis for the aerodynamics of wings is separated in two steps.now, we are going on the second-step in Prandtl's philosophy of wing theory

如上图所示的斜激波在真实情况下有时会碰到固壁或与其它激 波、膨胀波相交,进而发生相互作用,这种现象称为激波的干 扰与反射。本节的目的就是要定性地讨论激波的干扰问题