New method for detonation initiation induced by curved shock wave

Oblique wedge initiation is the predominant initiation mode for oblique detonation waves. While increasing the angle of the oblique wedge accelerates detonation, it also raises the overdrive degree of the detonation wave and the resistance within the combustion chamber. To simultaneously ensure rapid detonation initiation and combustion performance, we present the S-shaped wall initiation method, making full use of the flexibility of the curved shock wave system. Concave wall compression facilitates detonation initiation, while convex wall expansion mitigates the overdrive degree of the detonation wave. Given that the expansion wave affecting the initiation zone could lead to detonation wave extinguishment, precise adjustment of the turning point for the S-shaped wall initiation method becomes crucial. Thus, employing the method of curved-shock characteristics, we present a calculation approach to determining the initiation position of curved detonation, to establish the turning point of the S-shaped curved wall in a rational manner. Findings reveal that the optimized S-shaped wall initiation scheme leads to a 16.5% increase in average thrust potential gain and an 8.3% enhancement in the average total pressure recovery coefficient.