5.1 ABSTRACT Supersonic combustion data obtained at the low static temperatures appropriate for an efficient scramjet engine are reviewed. Attention is directed at the methods by which the fuel was ignited and combustion maintained. The cited supersonic combustion experiments are grouped under the six headings: chemical intiators; non-uniform flows; turbulent flameholding; combustion induced co...

Combustion and evaporation processes occurring in a closed chamber can result in significant pressure rise and direct work transfer. The pressure and volumetric changes that accompany such processes allow substantial work potential to be achieved in cyclic nonsteady devices, such as internal combustion engines and pulsed combustion or detonation engines. The ideal pressure gain or work producti...

Combustion analysis has been conducted on a small two-stroke glow ignition engine, which has similar combustion characteristics to homogeneous charge compression ignition (HCCI) engines. Difficulties such as unknown ignition timing and the polytropic index have been addressed by combining both heat release and mass fraction burn analyses. Results for all operating conditions have shown good cor...

The control of disturbances due to fuel quality variation is important development area in the grate combustion technology. Main challenges in the control of the grate combustion are inhomogeneous fuel, variation in fuel moisture content, non-uniform distribution of fuel on the grate area and high percentage of combustibles in ash. Information on events which occur in the furnace plays an impor...

Scalar dissipation rate is an essential parameter in combustion theory; understanding its behavior is necessary for developing and improving combustion models. In most cases, the scalar dissipation rate shows different trends under different combustion conditions, and it is thus case-dependent. Spray combustion is categorized as a partially-premixed combustion system, leading to very complex pr...

Amajor goal of combustion research is to develop accurate, tractable, predictive models for the phenomena occurring in combustion devices, which predominantly involve turbulent flows. With the focus on gasphase, non-premixed flames, recent progress is reviewed, and the significant remaining challenges facing models of turbulent combustion are examined. The principal challenges are posed by the ...

The development and implementation of a diesel engine combustion system simulation model is described. The model is a crank angle based combustion model, which uses the conditions in the intake and exhaust manifolds together with the fuel injection signal from the engine control unit to estimate the in-cylinder pressure throughout a complete combustion cycle. The model is implemented in Matlab....

-The role which low-temperature catalytic combustion should play in the future hydrogen energy system is discussed in comparison with those of conventional flame-type combustion and fuel cells. A hybrid of catalytic and flame combustion is also referred to in the comparison. Screening of catalyst materials proved that several inexpensive oxides of the 3d transition metals were active at interme...

Detailed models of combustion instability based on chemistry dynamics are developed. The results show that large activation energy goes against the combustion stability. The heat transfer coefficient between the wall and the combust gas is an important bifurcation parameter for the combustion instability. The acoustics modes of the chamber are in competition and cooperation with each other for ...

The analysis of soot formation and oxidation is essential for Diesel engine development to meet future pollutant emission reduction requirements. In recent years laser-induced incandescence (LII) has developed to a powerful tool for soot diagnostics in flames, even in the challenging environment of Diesel combustion. This work presents some recent applications of LII for soot particle sizing in...