The dual-fuel diesel engine (D.F.D.E) is a conventional diesel engine in which much of the energy released, hence power, comes from the combustion of gaseous fuel such as natural gas. The exhaust emission characteristics of the D.F.D.E needs further refinements, particularly in terms of reduction of Unburnt Hydrocarbons (U7HC) and Carbon Monoxide (CO) emission, because the concentration of thes...

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 methods for the time-dependent numerical solution of a two-dimensional model governing combustion in inert porous media. The spatial discretization is based on a mixed nite element method for the ow problem and a cell-centered nite volume scheme for the transport equations. Some results of numerical simulations show the innuence of a jump in the porosity of the solid matrix ...

As part of the VECTIS code validation programme, CFD simulations were conducted to investigate direct-inject (DI) diesel engine combustion with the newly implemented Ricardo Two-Zone Flamelet (RTZF) combustion model. A small HSDI research engine was chosen as subject. The simulation programme consisted of 6 cases forming a complete injection time swing. CFD simulation results were compared dire...

The combustion mechanisms of clouds of metal particles are addressed in this research. A microgravity environment was used to create a “stationary model aerosol” consisting of relatively large (100–300 mm diameter), initially motionless particles. The development of individual particle flames, motion of individual particles, and overall aerosol combustion process could be observed simultaneousl...

We derive analytical expressions for the propagation speed of downward combustion fronts of thin solid fuels with a background flow initially at rest. The classical combustion model for thin solid fuels that consists of five coupled reaction-convection-diffusion equations is here reduced into a single equation with the gas temperature as the single variable. For doing so we apply a two-zone com...

A most widespread method for coal gasification is the use of fluidized bed reactors. A new concept in recirculating fluidized bed gasification is the Judd twocompartment gasifier. The two compartments provide separated zones for gasification with steam and for combustion with air, within the same vessel. The circulation of inert solids transmits the heat from the combustion zone into the gasifi...