Effects of sample orientation on radiative ignition

Journal Article · Fri Jan 01 04:00:00 EST 1982 · Combust. Flame; (United States)

DOI:https://doi.org/10.1016/0010-2180(82)90075-X· OSTI ID:5287843

Kashiwagi, T

The effects of sample orientation on autoignition delay times and the minimum external radiant flux for autoignition were studied using a CO/sub 2/ laser and a gas fired radiant panel as external radiant sources with PMMA and red oak as samples. Ignition delay times were shorter with the horizontal sample than with the vertical one at the same external radiant flux. The minimum external radiant flux for ignition was also less with the horizontal sample. The absorption of external radiation by the boundary layer of decomposition products for the vertical orientation is significant, although its amount is less than the absorption through the plume for the horizontal orientation. Surface temperature at ignition is higher with vertical sample orientation than with horizontal at the same external radiant flux. A theoretical calculation of the surface temperature history with endothermic gasification significantly underestimates the experimental results; this raises a question of the applicability of regression rate expression derived from steady state experiments to the dynamic heating condition. 18 refs.

• Research Organization: NBS, Washington, DC
• OSTI ID: 5287843
• Journal Information: Combust. Flame; (United States), Journal Name: Combust. Flame; (United States) Vol. 44:1-3; ISSN CBFMA
• Country of Publication: United States
• Language: English

Related Subjects

09 BIOMASS FUELS
090400 -- Solid Waste & Wood Fuels-- (-1989)
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400800* -- Combustion
Pyrolysis
& High-Temperature Chemistry
CARBON DIOXIDE LASERS
CHEMICAL REACTION KINETICS
COMBUSTION KINETICS
ESTERS
GAS LASERS
HEATING
IGNITION
KINETICS
LASERS
ORGANIC COMPOUNDS
ORGANIC POLYMERS
ORIENTATION
PMMA
POLYACRYLATES
POLYMERS
POLYVINYLS
RADIATION HEATING
REACTION KINETICS
WOOD