On the dynamic detonation parameters in acetylene–oxygen mixtures with varying amount of argon dilution

Abstract

In this investigation, the dynamic detonation parameters for stoichiometric acetylene-oxygen mixtures diluted with varying amount of argon are measured and analyzed. The experimental results show that the critical tube diameter and the critical energy for direct initiation of spherical detonations increase with the increase of argon dilution. The scaling behavior between the critical tube diameter dc and the detonation cell size λ as well as the critical direct initiation energy Ec is systematically studied with the effect of argon dilution. The present results again validate that the relation dc = 13λ holds for 0% -30% argon diluted mixtures and breaks down when argon dilution increases up to 40%. It is found that the explosion length scaling of Ro ~ 26λ becomes also invalid when the mixture contains approximately this same amount of argon dilution or more. This critical argon dilution is indeed close to that found from experiments in porous-walled tubes by which exhibit a distinct transition in the failure mechanism. Cell size analysis in literature also indicates that the cellular detonation front starts to become more regular (or stable) when the argon dilution reaches more than 40 -50%.Regardless of the degree of argon dilution or mixture sensitivity, the phenomenological model developed from the surface energy concept by Lee, which provides a relation that links the critical tube diameter and the critical energy remains valid. The present experimental results also follow qualitatively the observation from chemical kinetic and detonation instability analyses.

Numerical study on initiation of oblique detonations in hydrogen–air mixtures with various equivalence ratios

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Detonation and deflagration characteristics of p-Xylene/gaseous hydrocarbon fuels/air mixtures

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“…Various levels of description of acetylene ignition and detonation chemistry were generated for computational and theoretical studies of high-temperature ignition and detonation behavior of fuels that contain or produce appreciable amounts of acetylene. These have mostly been validated and optimized for detonation simulations in gaseous hydrocarbon mixtures, which are also verified in our recent investigation [29] for studying the effect of varying argon dilution on the dynamic parameters of acetylene-oxygen-argon detonations.…”

Effects of argon/nitrogen dilution on explosion and combustion characteristics of dimethyl ether–air mixtures

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