A numerical investigation of surface tension and forced convection effects on moving and suspended methanol droplets burning in a zero-gravity, low-pressure air environment is presented. Simulations were conducted using a predictive, transient, axisymmetric model for an initial droplet diameter of 0.5 mm, an ambient temperature of 1200 K, and initial Reynolds numbers (Re0) in the range of 1 to ...

In this paper, a flame retardant dimethyl-2-(methacryloyloxyethyl) phosphate (DMMEP) was applied to wool fabrics by the graft copolymerization technique initiated with potassium persulfate (KPS) in water media. FTIR and SEM testing were used to explore the grafting evidence on the fiber surface, the SEM results show chemical deposition on the wool fiber surface and the scales could not be seen ...

A generalized formulation of combustion-acoustic coupling at simultaneous multiple timeand length-scales is presented. The compressible Navier Stokes equations are expanded about the mean flow Mach number M and the ratio of flow and acoustic length scales h/L. This results in the equations separating into the one governing the incompressible base flow evolving at longer time and shorter length ...

A novel one-step, vapor-fed aerosol flame synthetic process (VAFS) has been developed to prepare Ti(3+) self-doped titanium dioxide (TiO2). The freshly formed TiO2 was in situ surface hydrogenated during the condensation stage by introducing H2 above the flame, and Ti(3+) ions were created near the surface of TiO2. The relative content of Ti(3+) ions near the surface of TiO2 is estimated to be ...

The propagation of cellularly stabilized thermonuclear flames is investigated by means of numerical simulations. In Type Ia supernova explosions the corresponding burning regime establishes at scales below the Gibson length. The cellular flame stabilization—which is a result of an interplay between the LandauDarrieus instability and a nonlinear stabilization mechanism—is studied for the case of...

Turbulent methane flames exhibit a change in Markstein number as the equivalence ratio changes. In this paper, we demonstrate how these changes in Markstein number are related to shifts in the chemistry and transport. We focus on the analysis of simulations of two-dimensional premixed turbulent methane flames at equivalence ratios φ=0.55 and φ=1.00 computed using the GRI-Mech 3.0 mechanism. The...

Three-dimensional direct numerical simulations (DNS) of two different flow configurations have been performed for premixed flames interacting with chemically inert isothermal walls at the unburned gas temperature in fully developed turbulent boundary layers . The first configuration is an oblique flame-wall interaction (FWI) a V-flame channel and second head-on quenching planar flame layer. The...

The present protocol presents a laboratory technique designed to study chaparral crown fire ignition and spread. Experiments were conducted in a low velocity fire wind tunnel where two distinct layers of fuel were constructed to represent surface and crown fuels in chaparral. Chamise, a common chaparral shrub, comprised the live crown layer. The dead fuel surface layer was constructed with exce...

In a recent numerical paper (Nicoli et al. Combust. Sci. Technol. vol. 186, pp. 103-119; 2014) [1], a model of isobaric flame propagation in lean sprays has been proposed. The initial state of the monodisperse mists was schematized by a system of individual alkane droplets initially located at the nodes of a facecentered 2D-lattice, surrounded by a saturated mixture of alkane and air. In the pr...