Extinction limits and flame bifurcation of lean premixed dimethyl ether-air flames are investigated numerically using the counterflow flame with a reduced chemistry. Emphasis is paid to the combined effect of radiation and flame stretch on the extinction and flammability limits. A method based on the reaction front is presented to predict the Markstein length. The predicted positive Markstein l...

This paper describes the non-linear dynamics of premixed flames responding to harmonic velocity disturbances. It extends a prior computational study which determined the key parameters influencing the nonlinear flame characteristics. It was shown that the linear and nonlinear characteristics of the flame dynamics were controlled by the superposition of two sources of flame disturbances: those o...

The spatial resolution requirements of the Stochastic Fields probability density function approach are investigated in the context of turbulent premixed combustion simulation. The Stochastic Fields approach is an attractive way to implement transported Probability Density Function modelling into Large Eddy Simulations of turbulent combustion. In premixed combustion LES, the numerical grid shoul...

9 We report a simple fabrication technique of polymer microfibers with high surface smoothness and length uni10 formity using a molten polymethylmethacrylate in conjunction with direct drawing technique. With the aid of 11 fabricated polymer microfibers, we successfully demonstrate a new splicing technique via a two-step process. The 12 fabricated microfibers with diameter of 1.5 μm and length ...

In this study, the effect of flame intrinsic instability on the flame structural characteristics of hydrogen/air mixtures premixed at various equivalence ratios were experimentally investigated from the macroscopic and microscopic perspectives, respectively. The correlation degree and the relative deformation degree were defined to quantitatively study the global flame structural characteristic...

The rapid formation of tungsten oxide nanorods through electron beam (EB) irradiation on the surface of micron-sized flame formed tungsten-oxide fragments is reported. The micro-sized fragments (precursor material) were formed in a counter-flow methane diffusion flame on the surface of a tungsten wire. Nanorods of various lengths and aspect ratios were rapidly formed in the surrounding area of ...

This research focuses on the use of Esri’s ArcFuels and Missoula Fire Sciences Laboratory’s FlamMap to produce a wildfire exposure analysis on structures affected by the Charlotte Fire. Exposure analysis involves producing both conditional flame length and burn probability, which are combined to determine a structure’s wildfire risk. The individual datasets within the model were tested for accu...

An experimental and theoretical investigation of free turbulent premixed flames propagating in isotropic turbulence at neutrally stable preferential diffusion conditions is described. Experiments were limited to the wrinkled thin laminar ftamelet regime and involved mixtures of hydrogen, air, and nitrogen ignited within a fan-stirred combustion chamber. Measurements included flame tomography fo...