The use of a noble gas as an inert tracer for mixing studies in combustion systems is investigated. Simultaneous two-photon laser-induced fluorescence (LIF) of krypton and Rayleigh scattering are used for imaging measurements of mixture fraction and temperature in turbulent non-premixed jet flames. The turbulent flames investigated in this study include a piloted CH4/air flame (Sandia flame D) ...

In a recent numerical paper (Nicoli et al. Combust. Sci. Technol. vol. 186, pp. 103-119; 2014) [1], a model of isobaric flame propagation in lean sprays has been proposed. The initial state of the monodisperse mists was schematized by a system of individual alkane droplets initially located at the nodes of a facecentered 2D-lattice, surrounded by a saturated mixture of alkane and air. In the pr...

An adequate treatment of thermal radiation heat transfer is essential to a mathematical model of the combustion process or to a design of a combustion system. This paper reviews the fundamentals of radiation heat transfer and some recent progress in its modeling in combustion systems. Topics covered include radiative properties of combustion products and their modeling and methods of solving th...

A laboratory combustor was used to investigate the factors that influence the conversion of fuel nitrogen in coal during coal combustion. Fuel NO was isolated by experimentation utilizing Argon/Oxygen/Carbon Dioxide mixtures as the oxidant, and care was taken to compare cases with air at matched conditions. For both well mixed and slowly mixed flame types, fuel NO contributed over 75% of the to...

This study was aimed to determine combustion characteristics and decay resistance of Spruce [Picea orientalis (L.)], Fir (Abies nordmanniana), Alder [Alnus glutinosa (L.)], and Iroko (Milicia excelsa) woods impregnated with ammonium tetrafluoro borate (1 to 3%) and the mixture of cement and borax (6% to 9%). The combustion test method was performed in three stages: flame stage, without flame st...

Steady-state concentrations of electronically excited CH(AD) and OH(A¥) are extracted from previous quantitative measurements of optical emission from an axisymmetric laminar diffusion flame [K. T. Walsh, M. B. Long, M. A. Tanoff, and M. D. Smooke, Twenty-Seventh Symposium (International) on Combustion, The Combustion Institute, Pittsburgh, 1998, pp. 615–623]. The flame is modeled with a two-di...

Spray combustion is encountered in many engineering applications, such as internal combustion engines and gas-turbine aircraft engines. In these systems, the concurrent processes of liquid atomization, droplet evaporation, turbulent dispersion, and combustion interact and strongly affect each other, which makes experimental measurement and high-fidelity simulation challenging. To understand the...

To better understand the combustion chemistry of tetrahydrofuran (THF) and 2-methyltetrahydrofuran (MTHF) which has been considered as promising bio-fuel, the structure of their stoichiometric (φ=1.0) low-pressure laminar premixed flame has been investigated. The flames have been stabilized on a burner at a pressure of 50 Torr (6.7 kPa) using argon as dilutant (78 %), with a gas velocity at the...

Laser ignition has been discussed widely as a potentially superior ignition source for technical appliances such as internal combustion engines. Ignition strongly affects overall combustion, and its early stages in particular have strong implications on subsequent pollutant formation, flame quenching, and extinction. Our research here is devoted to the experimental investigation of the early st...

A high-order scheme for direct numerical simulations of turbulent combustion is discussed. Its implementation in the massively parallel and publicly available PENCIL CODE is validated with the focus on hydrogen combustion. This is the first open source DNS code with detailed chemistry available. An attempt has been made to present, for the first time, the full set of evolution and auxiliary equ...