English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

In this paper we formulate and analyze an elementary model for thepropagation of advancing autoignition fronts in reactive co-flow fuel/oxidizerjets injected into an aqueous environment at high pressure. This work ismotivated by the experimental studies of autoignition of hydrothermal flamesperformed at the high pressure laboratory of NASA Glenn Research Center. Guidedby experimental observations, we use several simplifying assumptions that allowthe derivation of a simple, still experimentally feasible, mathematical modelfor the propagation of advancing ignition fronts. The model consists of asingle diffusion-absorption-advection equation posed in an infinite cylindricaldomain with a non-linear condition on the boundary of the cylinder anddescribes the temperature distribution within the jet. This model manifests aninterplay of thermal diffusion, advection and volumetric heat loss within afuel jet which are balanced by the weak chemical reaction on the jet'sboundary. We analyze the model by means of asymptotic and numerical techniquesand discuss feasible regimes of propagation of advancing ignition fronts. Inparticular, we show that in the most interesting parametric regime when theadvancing ignition front is on the verge of extinction this model reduces to aone dimensional reaction-diffusion equation with bistable non-linearity. Wehope that the present study will be helpful for the interpretation of existingexperimental data and guiding of future experiments.

An elementary model for an advancing autoignition front in laminar reactive co-flow jets injected into supercritical water