the paper presents results of experimental studies on the methane and propane ignition process in various volumetric compositions of oxidizers heated to temperatures higher than ignition point of analyzed fuels (htac conditions–high temperature air combustion conditions). the increment of temperature dt and the ignition delay time tig are parameters characterizing the process of ignition under ...

The objective of this work is to investigate the spray ignition characteristics of diesel and canola-derived biodiesel in a rapid compression machine at the low temperatures (676 816 K) and reduced oxygen concentrations (12 and 18%) that are used in low-temperature combustion strategies of advanced diesel engines. A method for testing ignition delay times and apparent heat release rates at a se...

An empirical model for the ignition of aluminum particle clouds is developed and applied to the study of particle ignition and combustion behavior resulting from explosive blast waves. This model incorporates both particle ignition time delay as well as cloud concentration effects on ignition. The total mass of aluminum that burns is found to depend on the model, with shorter ignition delay tim...

A kinetic mechanism of 1011 elementary reactions with 171 chemical species for n-heptane ignition is analysed and reduced to 4 global steps with adjusted rate coefficients to describe ignition at pressures around 40 atm. Two of these steps account for the high temperature branch and the other two for the low temperature branch of the ignition mechanism. The ignition delay time passes through a ...

The prediction of the auto-ignition delay time of fresh fuel in hot air is studied. This problem, encountered in many combustion systems, is in practice often calculated using a simple method, hereafter called homogeneous mixing ignition (HMI). This method however neglects transport effects and calculates local instead of global ignition properties. A second method is therefore studied called l...

Autoignition of a hydrogen-air scalar mixing layer in homogeneous turbulence is studied using direct numerical simulation (DNS). An initial counterflow of unmixed nitrogen-diluted hydrogen and heated air is perturbed by two-dimensional homogeneous turbulence. The temperature of the heated airstream is chosen to be 1100 K, which is substantially higher than the crossover temperature at which the...

Ignition and burning characteristics of single aluminum and magnesium particles are experimentally investigated. Burning time, ignition delay, flame temperature, and ignition temperature were measured. The single metal particle (30-100 μm in diameter) is uplifted by an electrodynamic levitator, exposed and ignited by a CO2 laser. The thermal radiation intensity was measured using the photomulti...