Accelerated initiation of oblique detonation induced by disturbance in detonative zone

Abstract

In the real flow for high altitude, the initiation mechanism of the oblique detonation involves the coupling of complex wave structures and combustion waves, which may result in the phenomenon of extinction. The approach of stable initiation is one of the key factors that restricting the oblique detonation engine from theory to practice. The wave structure, initiation characteristics and characteristic parameters of the flow field are analyzed, the two-dimensional Euler equation considering the detailed chemical reactions of multi-component are solved. First, the approaches of blunt bump and transverse jet are combined used to shorten the detonation distance of the oblique detonation. Results show that these methods can promote the accelerated initiation of the oblique detonation effectively, and the detonation distance can be shortened more than 90%. There are two wave structures induced by the blunt bump: weak coupled and strong coupled, adding the transverse jet promotes the transition between these two wave structures. Then, the shape of the bump and the characteristic parameters of the transverse jet are optimized. The streamline-shape bump can eliminate the recirculation zone formed after the circle bump and the ellipse bump. The transverse jet will produce an oblique detonation wave at the front of the jet position, which changes the wave structure and initiation mode of the oblique detonation wave. Through the research of this project, it is expected to reveal the accelerated initiation mechanism of oblique detonation under the induction zone disturbance and complex flow environment, deepen the understanding of the detonation law of oblique detonation wave under real flow conditions, and provide a scientific basic for the development of the combustor of the oblique detonation engine.

Topics & Concepts