Theoretical investigation of piloted ignition of wood

Technical Report · Thu Aug 01 04:00:00 EDT 1991

OSTI ID:6245309

Tzeng, L S; Atreya, A

A theoretical model for piloted ignition of a flame in the gas phase above a vaporizing or pyrolyzing solid has been developed. Using the model it has been found that (1) The postulated simplified governing equations adequately explain the pre-ignition flashes that are often observed experimentally; (2) A rational criterion for positioning the pilot flame exists; (3) The heat losses to the surface play an important role, indicating that the fuel evolution rate by itself is insufficient for predicting the onset of piloted ignition. In the investigation, a numerical integration scheme is developed that accounts for the often vastly different rates between chemical reaction and convection or diffusion processes in the equations of combustion theory. The new numerical scheme is found to be very efficient for the piloted ignition problem, which involves both pre-mixed and diffusion flames. Finally, a numerical model for piloted ignition of wood which includes transient solid-phase decomposition has been developed. It has been found that the activation energy for the combustion of the evolved fuel is 49 Kcal/mole.

• Research Organization: Michigan State Univ., East Lansing, MI (United States). Dept. of Mechanical Engineering
• OSTI ID: 6245309
• Report Number(s): PB-92-112432/XAB; CNN: NANB8D0861
• Country of Publication: United States
• Language: English

Related Subjects

09 BIOMASS FUELS
092000* -- Biomass Fuels-- Combustion-- (1990-)
ACTIVATION ENERGY
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
COMBUSTION
COMBUSTION KINETICS
DECOMPOSITION
DIFFUSION
ENERGY
ENERGY SOURCES
ENERGY TRANSFER
EQUATIONS
FLAME PROPAGATION
FLAMES
FLUIDS
FUELS
GASES
HEAT TRANSFER
IGNITION
KINETICS
MATHEMATICAL MODELS
MATTER
OXIDATION
PYROLYSIS
PYROLYSIS PRODUCTS
PYROLYTIC GASES
REACTION KINETICS
SOLIDS
THERMOCHEMICAL PROCESSES
VOLATILE MATTER
WOOD FUELS