The objective of this work was to investigate the influence of preferential diffusion on flame structure and propagation of lean-premixed hydrogen-carbon monoxide syngas-air flame at elevated pressure using direct numerical simulation (DNS) and detailed chemistry. The physical problem investigated is lean-premixed H2/CO outwardly propagating turbulent spherical flame at constant pressure of 4ba...

Background: Radioactive yttrium glass microspheres are used for liver cancer treatment. These yttrium aluminum silicate microspheres are synthesized from yttrium, aluminum and silicone oxides by melting. There are two known processes used to transform irregular shaped glass particles into microspheres, these ‘spheroidization by flame’ and ‘spheroidization by gravitational fall...

Rapid suppression is a must in the mitigation of ventilation air methane (VAM) explosions. Flame proves to be much more challenging than prevention flame initiation due small physics timescale (~1 s). This study numerically investigates effect spherical obstructions on propagation dynamics tube closed at one end. Obstructions with an inflating geometry, installed different locations, were exami...

The downsized spark ignition (SI) engine is considered as one promising technology to reduce pollutants and greenhouse gas emissions. By boosting the intake air pressure, this operating mode achieves higher efficiency, thus reducing pollutant Modeling combustion process in these drastic conditions (high high temperature dilution rate) remains challenging, however, since most of models premixed ...

Radiative energy losses induce instability and extinction of low-momentum microgravity diffusion flames. In this work, the critical condition steady flame to exist a correlation for pre-extinction size self-extinguished flames are derived using temperature concept considering balance. With values 1100 K ethylene, 1200 propane, 1300 methane flames, favorable performance is demonstrated in predic...

The flame stability limit, which was involving the critical flow condition, lift off and blow out, could be affected by the burner geometry in the combustion system installation. Consequently a flame holder should be put in, to hold the flame as big as possible on a stable condition. The flame holder itself, is a device to hold the flame, whereas the flame holder could disturb the air and fuel ...

Soot formation in premixed laminar flames is examined for a canonical set of burning C6 hydrocarbon fuels. Particle mobility size and flame temperature measurements are complemented by structure calculations using detailed chemistry. Specifically, the evolution soot particle distribution (PSDF) compared n-hexane, n-hexene, 2-methylpentane, cyclohexane benzene at carbon-to-oxygen ratio 0.69 maxi...

The four processes involved in the flammability of materials are described and related to the various flame retardance mechanisms that may operate. Following this the four practical approaches used in improving flame retardance of materials are described. Each approach is illustrated with a number of typical examples of flame retardants or synthetic procedures used. This overview of flammabilit...