Study of the combustion characteristics of liquid N-heptane in a tiny straight tube type burner

To learn the flame extinction and diffusion characteristics of liquid fuel in a micro space, various sleeve tubes and porous media were used. In a tiny straight tube, the diffused flame of heptane was experimentally studied. The research results show that with an increase of the flow rate of heptane, the stable location of the flame will gradually move to the outlet of the straight tube type burner, the flammable limits will first become wide at a high speed and then tend to be constant. To increase the number of the sleeve tubes can effectively expand the flammable limits and the structure of the sleeve tubes has a big influence on the flame stability and flammable limits. The more the number of the sleeve tubes, the smaller the heat quantity released from the burner. In addition, the location of the porous medium influences greatly the flame stability. When the nozzle of heptane is placed at the upper reaches of the porous medium or in it, the evaporation and mixing effectiveness of liquid heptane will be the best, thus obtaining a better oxygen-enriched combustion limit.