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arXiv · 2509.10169

Convective flux analysis on the instability of one-dimensional detonation

Yunfeng Liu
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Abstract

One-dimensional numerical simulations using the Euler equations and irreversible one-step Arrhenius kinetics are conducted to study the instability mechanism of a one-dimensional gaseous detonation. By increasing the activation energy, this study identifies the characteristics of stable detonation, periodic detonation, pulsating detonation, and detonation quenching. The key difference between this study and previous research is that it is the first quantitative analysis of convective flux, kinetic energy flux, and chemical reaction heat flux. These three fluxes undergo intensive change on the detonation front and the flow field at each time step depends on the algebra summation of them. The mechanisms of detonation instability, detonation reignition and detonation quenching process can be revealed quantitatively by analyzing these fluxes.

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Yunfeng Liu. 2025-09-12. Convective flux analysis on the instability of one-dimensional detonation. https://arxiv.org/abs/2509.10169

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