In order to improve the efficiency of intumescent flame retardants (IFRs), a novel macromolecular charring agent named poly(ethanediamine-1,3,5-triazine-p-4-amino-2,2,6,6-tetramethylpiperidine) (PETAT) with gas phase and condense phase synergistic flame-retardant capability was synthesized and subsequently dispersed into polypropylene (PP) in combination with ammonium polyphosphate (APP) via a ...

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...

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...

In this paper, we review the present state of theoretical models of thermonuclear supernovae, and compare their predicitions with the constraints derived from observations of Type Ia supernovae. The diversity of explosion mechanisms usually found in one-dimensional simulations is a direct consequence of the impossibility to resolve the flame structure under the assumption of spherical symmetry....

The control of ignition in a rocket engine is a critical problem for combustion chamber design. Delayed ignition may lead to high amplitude pressure fluctuations that can damage the burner (strong ignition) whereas early ignition may fail. This paper describes a numerical study of a strong ignition sequence observed in a laboratoryscale single-injector rocket chamber ignited by a laser and fuel...

In this study a new formulation of the unsteady flamelet model is derived to account for the locally resolved distribution of the scalar dissipation rate obtained from large-eddy simulations (LES). Starting from the unsteady flamelet equations, a transformation leads to an Eulerian flamelet model, in which the scalar dissipation rate appears as function of time, space, and mixture fraction. In ...

Due to its environmentally benign character, supercritical carbon dioxide (scCO2) is considered in green chemistry, as a substitute for organic solvents in chemical reactions. In this paper, an innovative approach for preparation of flame retardant cotton fabric was obtained by utilizing supercritical carbon dioxide with co-solvent. A novel phosphorusnitrogen containing piperazine derivative, t...