The influence of a turbulent spectrum of the temperature field on compression ignition at constant volume under homogeneous charge compression ignition engine conditions is studied by direct numerical simulation with complex chemistry. In particular the dependence of overall ignition progress on initial mixture conditions and turbulence parameters is determined. The propagation speed of ignitio...

Title of Document: PROBING THE IGNITION MECHANISM OF ALUMINUM NANOTHERMITES Snehaunshu Chowdhury, Ph.D., 2012 Directed By: Professor Michael R. Zachariah, Department of Mechanical Engineering, Chemistry and Biochemistry Nanothermites are defined as intimate mixtures of metal and metal oxidizer particles usually below 100 nm in diameter. They belong to a class of energetic materials which have b...

The development of modern vehicle drives is aimed at reducing fuel consumption (i.e., crude oil) and minimizing the exhaust emission toxic components. One such implementation a two-stage combustion system. Such system initiates ignition in prechamber, then burning mixture flows into main chamber, where it ignites lean mixture. allows efficient mixtures, both liquid gaseous fuels, cylinder. This...

homogeneous charge compression ignition (hcci) combustion is a pioneer method of combustion in which pre-mixed fuel and oxidizer (typically air) are compressed to the point of auto-ignition. hcci engines can operate with most alternative fuels, especially, dimethyl ether (dme) which has been tested as a possible diesel fuel due to its simultaneously low nox and pm emissions. in this paper a sin...

This paper presents study of a 6.78 MHz RF source with impedance matching network based inductively coupled plasma generator ignition system for an Hion source. Two types of 10 turn RF antenna (solenoid coil) were developed, to couple the RF power to the ignition plasma chamber. The antenna’s electric parameters were measured using Vector Network Analyzer (VNA). A copper conductor of 3 x 4 mm s...

Wildfire ignition distributionmodels are powerful tools for predicting the probability of ignitions across broad areas, and identifying their drivers. Several approaches have been used for ignition-distribution modelling, yet the performance of different model types has not been compared. This is unfortunate, given that conceptually similar speciesdistributionmodels exhibit pronounced differenc...

The issue of spontaneous ignition of highly pressurized hydrogen release is of important safety concern, e.g. in the assessment of safety risk and design of safety measures. This paper reports on recent numerical investigation of this phenomenon through releases via a tube using a 5-order WENO scheme. A mixture-averaged multi-component approach was used for accurate calculation of molecular tra...