Journal of the Korean Society of Combustion (한국연소학회지)

The Korean Society of Combustion (한국연소학회)
권호 표지

The Influence of Magnetic Field on Diffusion Flames: Role of Magnetic Field On/Off Frequency and Duty Ratio

자기장 분포가 확산화염의 연소특성에 미치는 영향: 자기장 On/Off 주기와 Duty Ratio의 역할

  • Received : 2012.02.27
  • Accepted : 2012.03.21
  • Published : 2012.03.30
Download PDF
⟨ Previous Next ⟩

Abstract

The influence of magnetic field on propane and acetylene diffusion flames have been experimentally investigated using an electromagnetic system. Periodically induced magnetic field having various frequencies and duty ratios was established in square wave form. The maximum intensity and gradient of magnetic field were 1.3 T and 0.27 T/mm, respectively. The width of a propane flame was reduced up to 4.5% and the brightness was enhanced up to 25% when the magnetic field was induced. The soot emission from an acetylene flame was ceased when magnetic field was induced. The alteration of flow field, which is due to the paramagnetic characteristics of oxygen molecule, is most likely to be responsible for the change in flame size and brightness. The effect of magnetic field on diffusion flames, which competes with the gravitational effect, was more apparent from a smaller size flame. The magnetic field effect, therefore, could be important under microgravity conditions. Since the time required to alter the flow field must be finite, the magnetic field effect is likely to be less significant for a periodically oscillating magnetic field at a high frequency or having a small duty ratio.

Keywords

References

  1. Faraday, M., "On the diamagnetic condition of flame and gases", London Edinburgh and Dublin Philosophical Magazine and Journal of Science, Series, 1847, 331-210, 401-421
  2. N. I. Wakayama, I. Ogasawara, T. Nishikawa, Y. Ohyagi, and H. Hayashi, "Magnetic quenching of the emission intensities of HPO and SnH in hydrogen- oxygen flames", Chemical Physics Letter, Vol. 107, No. 2, 1984, 207-211 https://doi.org/10.1016/0009-2614(84)85701-2
  3. N.I. Wakayama, I. Ogasawara, and H. Hayashi, "The external magnetic field effect on the emission intensity of the Na D line in hydrogen-oxygen flames", Chemical Physics Letters, Vol. 105, No. 2, 1984, 209-213 https://doi.org/10.1016/0009-2614(84)85652-3
  4. N. I. Sorokin, N. M. Bazhin "Magnetic field effect on the emission intensity of alkali atoms in hydrogen-oxygen", Chemical Physics Letters, Vol. 138, No. 2, 1987, 170-174 https://doi.org/10.1016/0009-2614(87)80363-9
  5. N. I. Wakayama, "Magnetic promotion of combustion in diffusion flames", Combust. Flame, Vol. 93, 1993, 207-214 https://doi.org/10.1016/0010-2180(93)90103-A
  6. Wakayama, N. I., H. Ito, Y. Kuroda, O. Fujita, K. Ito, "Magnetic support of combustion in diffusion flames under microgravity", Combust. Flame, Vol. 107, 1996, 187-192 https://doi.org/10.1016/0010-2180(96)00053-3
  7. Fujita, O., K. Ito, T. Chida, S. Nagai, Y. Takeshita, "Determination of magnetic field effects on a jet diffusion flame in a microgravity environment", Proc. Combust. Inst. Vol. 27, 1998, 2573-2578
  8. J. Baker, M. E. Calvert, "A study of the characteristics of slotted laminar jet diffusion flames in the presence of non-uniform magnetic fields", Combust. Flame, Vol. 133, 2003, 345-357 https://doi.org/10.1016/S0010-2180(03)00021-X
  9. Shinoda, M., E. Yamada, T. Kajimoto, H. Yamashita, K. Kitagawa, "Mechanism of magnetic field effect on OH density distribution in a methane-air premixed jet flame", Proc. Combust. Inst. Vol. 30, 2005, 277-284
  10. Swaminathan, S., Effects of magnetic field on micro flames, M.S thesis, Louisiana State university, 2005.
  11. Mizutani, Y., M. Fuchihata, Y. Ohkura, "Pre-mized Laminar Flames in a Uniform Magnetic Field", Combust. Flame, Vol. 125, 2001, 1071-1073 https://doi.org/10.1016/S0010-2180(00)00244-3
  12. Wakayama, N. I., "Utilization of magnetic force in space experiments", Adv. Space Res. Vol. 24, No. 10, 1999, 1337-1340 https://doi.org/10.1016/S0273-1177(99)00743-7
  13. www.f-core.co.kr
  14. www.vizimag.com