Effects of ozone addition and LTC progression on detonation of O\(_{3}\)-enhanced DME–O\(_{2}\)

Abstract

The effects of ozone addition and low-temperature chemistry (LTC) progression on DME/O\(_{2}\) detonations are evaluated with experimental detonation velocity and cell size measurements and one-dimensional ZND simulations. For \( \phi = 1.2\) and \(P_{\textrm{o}}= 22.7\) kPa, detonations are experimentally investigated over a range of ozone enhancement levels (0.0–1.6-mol%), initial reactant temperatures (293 K and 468 K), and LTC progression times (250–6000 ms). A 33-K gas temperature rise from LTC heat release is observed for mixtures with 1.0-mol% ozone enhancement and initial temperature of 468 K, suggesting a limited extent of LTC progression in this study. Experiments showed minimal detonation velocity dependence on ozone enhancement level or LTC progression despite the increased radical pool. Average cell size is found to decrease 15–30% with 1.6-mol% ozone addition, indicating a greater reactant mixture sensitivity to detonation. To estimate the cell size, a center-of-exothermic-length induction length is defined and used with an empirical correlation to calculate a singular cell size when multiple thermicity peaks are present in ZND modeling. This approach shows good agreement with experimental findings. Cell size dependence on LTC progression is found to have a statistically insignificant variance for LTC progression times at the temperatures used in this study.