Low-temperature zone in a hydrocarbon flame front. Part 8: Effects of cyclohexyl nitrate on the structure of the flame front for hexane

Journal Article · Fri Jul 01 04:00:00 EDT 1983 · Combust., Explos. Shock Waves (Engl. Transl.); (United States)

DOI:https://doi.org/10.1007/BF00790228· OSTI ID:6546741

Manzhos, V K; Kolesnikov, B Y; Kopylova, L I; Ksandopulo, G I

In previous experiments, the authors described composition profiles for the initial substances and reaction products in the preflame zone for flames in mixtures of hexane with oxygen and argon. The addition of a chain initiator to the fuel intensifies the combustion. Amongst the numerous such substances, an unusual effect on the combustion rate is produced by cyclohexyl nitrate, which can act as a promoter or an inhibitor in accordance with the concentration in the fuel mixture. The composition and temperature profiles in the low-temperature zone for the flame from sprayed hexane are examined. The results indicate that the inhibition occurs in the hot zone near the luminous cone while promotion occurs in the cold zone. The production of active centers in the cold zone by reaction of H atoms with CHN and with products from the latter can accelerate the conversion of the hexane that occurs in the absence of the additive even if there is a reduction of the diffusion flux from the luminous zone. At larger amounts of the additive, there is a marked reduction in the diffusion flux of H atoms (because of the denser screen of NO and NO/sub 2/ in the hot zone), so the inhibition exceeds the promotion in the cold zone, and the overall effect is inhibition. The model provided may explain the numerous and often conflicting data on the effects of nitrogen oxides on ignition and combustion under various conditions.

• Research Organization: Alma-Ata
• OSTI ID: 6546741
• Journal Information: Combust., Explos. Shock Waves (Engl. Transl.); (United States), Journal Name: Combust., Explos. Shock Waves (Engl. Transl.); (United States) Vol. 19:1; ISSN CESWA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400800* -- Combustion
Pyrolysis
& High-Temperature Chemistry
ADDITIVES
ALKANES
CHALCOGENIDES
CHEMICAL COMPOSITION
CHEMICAL REACTION KINETICS
COMBUSTION KINETICS
DIFFUSION
ELEMENTS
FLAME PROPAGATION
FLAMES
HEXANE
HYDROCARBONS
HYDROGEN
IGNITION
INHIBITION
KINETICS
NITRATES
NITROGEN COMPOUNDS
NITROGEN OXIDES
NONMETALS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
REACTION KINETICS
TEMPERATURE GRADIENTS