Flame Propagation of Propane/Air Mixtures near flammability limits under gravity and microgravity conditions
- Paper number
IAC-08.A2.2.6
- Author
Dr. Jun Hu, Beijing Institute of technology, China
- Coauthor
Prof. Jozef Jarosinski, Technical University of Lodz, Lodz, Poland, Poland
- Coauthor
Prof. Yikang Pu, Institute of Mechanics, Chinese Academy of Sciences, China
- Year
2008
- Abstract
ABSTRACT Flame properties are very important characteristics concerning the combustion efficiency and industry safety for the flammable mixtures near flammability limits. A main effort devoted to the present study is to observe the behavior of flame propagating in rich propane-air mixtures in closed vessel under gravity and microgravity conditions, and clarify the differences between two conditions precisely. For this purpose a special designed Schlieren system and instant temperature measurement were adopted for obtaining precise observation results of flame shape and location during the flame propagating from ignition to extinction. Series experimental work was conducted under gravity and microgravity conditions with propane/Air mixtures near lean and rich flammability limits. The rich flammability limit of propane/air mixtures in closed vessel under gravity and microgravity conditions were determined directly not only by the derivative from the observations of flame propagating, but also confirmed by the measured pressure records of combustion process. The behaviors of flame propagating and the developments of combustion process with or without influence of buoyancy forces were demonstrated completely different. The relative relation between laminar burning velocity and buoyancy velocity is probably the main factor to create the above difference between two conditions. It was also found that at the lean flammability limit of propane/air mixtures there was practically no difference for flame propagation under two conditions from the point of view of gravity acceleration.
- Abstract document
- Manuscript document
(absent)