高超声速进气道/隔离段内流特性研究进展

Progress in Internal Flow Characteristicsof Hypersonic Inlet/Isolator

关键词:  高超声速进气道/隔离段  激波/边界层干扰  背景波系  角区旋涡  激波串

Key words:  Hypersonic inlet/isolator  Shock wave/boundary layer interaction  Background waves  Corner vortex  Shock train

摘要:

作为超燃冲压发动机的增压部件，高超声速进气道/隔离段内部存在一系列的复杂流动现象，本文概述了该领域的相关研究进展。高超声速进气道/隔离段内存在多种激波/边界层干扰现象，并受到膨胀波系等的干扰，使其特性偏离了传统基于简化模型的研究结果，具有显著的三维干扰特征、多波组合干扰特征，并在通道内诱导出了显著的二次流，特别是角区旋涡流动。隔离段内存在复杂的激波和膨胀波结构，这些背景波系在隔离段内不断反射，形成显著的流向和横向参数间断。当出口流道发生几何或热力壅塞时，隔离段内会出现更为复杂的激波串现象。激波串和上游背景波系、角涡相干，呈现出明显的偏向性，并在前移过程中可能会出现两种特殊的动态前移过程。尽管最近对高超声速进气道/隔离段内流特性的认识得到了极大地提高，但仍然有较多的基础问题亟待解决。

Abstract:

Inlet and isolator are the compression components of scramjet engines， the internal flows of which are fairly complicated. The latest research achievements focused on the internal flow of inlet/isolator are reviewed. Firstly， there are complex shock/boundary layer interactions in the inlet/isolator， and the interactions are affected by the expansion waves. The characteristics of the shock/boundary interactions depart from the canonical theories based on simplified model. The interactions behave quite three-dimensional and involve multiple shock waves/ boundary layers interaction， besides， the complex interactions will induce significant secondary flow， especially the corner vortex flow. Then， there are complex shock-expansion systems in the isolator， which reflect in the isolator leading to significant streamwise and transverse parameter discontinuities. In addition， when the exit flow path is mechanical or thermal choked， a more complicated flow phenomenon， named shock train， will appear. The shock train interacts with the upstream background waves as well as the corner vortex， and behaves directionality. When the shock train propagates upstream， two typical dynamic transitions may occur. Although the related knowledge of the internal flow characteristics of hypersonic inlet/isolator has been improved greatly， there still remain some basic problems to be uncovered in the future.