A one-step reduced chemical-kinetic mechanism describing near-critical hydrogen combustion, recently derived by assuming that all chemical intermediates maintain steady state, is used to investigate numerically the pulsating dynamics of fuel-rich hydrogen-air flames. The computations, considering pressures up 20 atmospheres, address flame evolution for increasing values equivalence ratio ϕ , a ...

in this paper, a new model based on kinetic theory of gases and longitude oscillations of metallic nanocluster on single carbon nanotube (cnt) in addition to phononvibrations of cnt on substrate is presented to describe the growth mechanism of ultra-long cnt in chemical vapor deposition (cvd).interaction between cnt and catalyst is investigated by lennard-jones potential. simulations demonstrat...

A detailed chemical kinetic model is presented for silicon oxide clustering that leads to particle nucleation during low-pressure silane oxidation. Quantum Rice–Ramsperger–Kassel theory was applied to an existing high-pressure silane oxidation mechanism to obtain estimates for the pressure dependence of rate parameters. Four classes of clustering pathways were considered based on current knowle...

A mathematical model for commercial naphtha catalytic reformer of Tehran refinery was developed. This model includes three sequencing fixed beds of Pt/Al2O3 catalyst at the steady state condition using detailed kinetic scheme involving 26 pseudo-components connected by a network of 47 reactions, in the range of C6 to C9 hydrocarbons. The reaction network consisted dehy...

Using quantum chemical methods, we have explored the region of the C6H8 potential energy surface that is relevant in predicting the rate coefficients of various wells and major product channels following the reaction between cyclopentadienyl radical and methyl radical, c-C5H5 + CH3. Variational transition state theory is used to calculate the high-pressure-limit rate coefficient for all of the ...

The detailed behavior of many molecular processes in the cell, such as protein folding, protein complex assembly, and gene regulation, transcription and translation, can often be accurately captured by stochastic chemical kinetic models. We investigate a novel computational problem involving these models - that of finding the most-probable sequence of reactions that connects two or more states ...

The research presented here describes the application of a multistep (8-step) autoignition model to oxygenated fuels such as alcohols and esters in a rapid compression machine. This modeling concept is aimed at capturing the ignition behavior of new oxygenated fuel blends, where detailed or reduced chemical kinetics data are not available. The predicted ignition delays from the multistep autoig...

In this paper, the gas-kinetic BGK scheme for the compressible flow equations is extended to chemical reactive flow. The mass fraction of the unburnt gas is implemented into the gas kinetic equation by assigning a new internal degree of freedom to the particle distribution function. The new variable can be also used to describe fluid trajectory for the nonreactive flows. Due to the kinetic gove...

In this study, strategies are proposed for modeling the input uncertainties in combustion calculations under chemical-rate uncertainties using as an example hydrogen-oxygen kinetics. For this purpose, this report is divided into the following sections. In Section 2, an assessment is made to ascertain the limitations of state-of-the-art treatments of experimentally-derived chemical-kinetic uncer...