鼓包诱导斜爆震波的数值研究

Numerical Study of Oblique Detonation Waves Induced by a Bump

关键词:  斜爆震发动机  鼓包  加速起爆  来流扰动  流动控制

Key words:  Oblique detonation wave engine  Bump  Initiation acceleration  Inflow disturbance  Flow control

摘要:

为实现低马赫数条件下斜爆震波的快速起爆，以及提高斜爆震波对来流扰动的抗干扰能力，提出了通过在诱导区内设置一个小鼓包来控制斜爆震波起爆的方案，并通过数值求解二维多组分欧拉方程研究了楔面和鼓包诱导的斜爆震波。结果表明：通过在诱导区内设置鼓包可实现斜爆震波的提前起爆；且在较宽马赫数范围内，其起爆位置相对固定。鼓包诱导的斜爆震波主要有强耦合和弱耦合两种起爆形式，起爆形式与鼓包和斜激波的相对位置有关。此外，来流扰动会使楔面诱导的斜爆震波剧烈振荡，不利于斜爆震发动机的稳定工作；鼓包的存在对来流扰动所引发的斜爆震波振荡具有一定的抑制作用。

Abstract:

In order to implement fast initiation of oblique detonation wave at low Mach numbers and to improve its capability of resisting disturbance to unsteady inflow， an idea of controlling initiation of oblique detonation wave by setting a small bump within its induction zone was proposed. Numerical simulations of oblique detonation waves induced by wedges and bumps were carried out by solving the two-dimensional multi-species Euler equations. Results show that initiation acceleration of oblique detonation wave can be implemented by setting a bump within the induction zone， and the initiation location keeps relatively fixed for a relative wide range of Mach number. There exist two initiation patterns for bump-induced oblique detonation wave， namely the strong coupled initiation and weak coupled initiation， depending on the location relationship between the bump and the oblique shock wave. Further， severe oscillation of wedge-induced oblique detonation wave would be induced by inflow disturbance， which is disadvantageous to the stable operation of oblique detonation engine. A certain inhibitory effect on the oscillation of oblique detonation wave induced by inflow disturbance can be observed with the inclusion of a bump.