층류 부상 화염의 화염부상 높이 감소 구간에서 교류 전기장이 인가된 화염에 관한 영향
Effect of AC Electric Field on Decreasing Liftoff Height in Laminar Lifted Jet Flames
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An experimental study has been conducted to elucidate the effect of AC electric field on behaviors of laminar lifted flame in nitrogen-diluted methane coflow-jets. Our concerns are focued on the regime to show a decrease in liftoff height, HL with increasing nozzle exit velocity, UO (hereafter, decreasing-HL). The HL with UO near flame extinction were measured by varying the applied AC voltage, VAC and frequency, fAC in a single electrode configuration. The behavior of HL with a functional dependency of VAC and fAC was categorized into two regime : (I) HL decreased for nozzle diameter, D = 1.0 mm, and (II) HL increased in the increase of fAC for a fixed VAC in a D = 4.0, 8.4 mm. The lifted flames in decreasing-HL region was unstable in high voltage regimes while the HL showed a decreasing tendency with UO except them. Such behaviors in HL were also characterized by functional dependencies of related physical parameters such as VAC, fAC, UO, fuel mole fraction (XF.O) and D.
Abstract
An experimental study has been conducted to elucidate the effect of AC electric field on behaviors of laminar lifted flame in nitrogen-diluted methane coflow-jets. Our concerns are focued on the regime to show a decrease in liftoff height, HL with increasing nozzle exit velocity, UO (hereafter, decreasing-HL). The HL with UO near flame extinction were measured by varying the applied AC voltage, VAC and frequency, fAC in a single electrode configuration. The behavior of HL with a functional dependency of VAC and fAC was categorized into two regime : (I) HL decreased for nozzle diameter, D = 1.0 mm, and (II) HL increased in the increase of fAC for a fixed VAC in a D = 4.0, 8.4 mm. The lifted flames in decreasing-HL region was unstable in high voltage regimes while the HL showed a decreasing tendency with UO except them. Such behaviors in HL were also characterized by functional dependencies of related physical parameters such as VAC, fAC, UO, fuel mole fraction (XF.O) and D.
참고문헌 (20)
- S. H. Won, "Effect of electric fields on the propagation speed of tribrachial flames in coflow jets", Combust Flame, 152, pp.496~ (2008)
- M. K. Kim, "Electric filed effect on liftoff and blow-off of nonpremixed laminar jet flames in a coflow", Combust Flame, 157, pp.17~ (2010)
- M. S. Cha, "Premixed Combustion Under Electric Field in a Constant Volume Chamber", IEEE Trans. Plasma Sci, 40, pp.3131~3138 (2012)
- Y. Xiong, "AC electric field induced vortex in laminar coflow diffusion flames", Proc. Combust. Inst., 35, pp.3513~3520 (2015)
- J. Lawton, "Electrical aspects of combustion", pp.283~ (1970), Clarendon Press
- F.J. Weinberg, "Advanced Combustion Method" (1989), Academic Press
- S. M. Lee, , IEEE Trans. Plasma Sci, 33(5), pp.1703~1709 (2005)
- S. H. Won, "Effect of electric field on reattachment and propagation speed of tribrachial flames in laminar coflow jets", Proc. Combust Inst, 31, pp.963~ (2007)
- S. K. Ryu, "Observation of multi-scale oscillation of laminar lifted flames with low-frequency AC electric fields", Combust. Flame, 157(1), pp.25~32 (2010)
- S. H. Chung, "On the Characteristics of Laminar Lifted Flames in a Non-premixed Jet", Combust. Flame, 86, pp.62~ (1991)
- B. J. Lee, "Stabilization of Lifted Tribrachial Flames in a Laminar Nonpremixed Jet", Combust. Flame, 109, pp.163~ (1997)
- S. H. Chung, "Stabilization, propagation and instability of tribrachial triple flame", Proc Combust Inst, 31, pp.877~ (2007)
- R. W. Bilger, "Stabilization mechanisms of lifted laminar flames in axisymmetric jet flows", Combustion and Flame, 122, pp.377~399 (2000)
- Narayan P. Sapkal, "A Study on Laminar Lifted Jet Flames for Diluted Methane in Co-flow Air", 한국연소학회지, 20(3), pp.1~7 (2015), 한국연소학회[DOI]
- N. P. Sarpkal, "Decreasing Liftoff Height Regions on Diluted Methane Co-flow Jet Flames", The 53th KOSCO Symposium (2016)
- S. H. Won, "Lifted Flame Stabilization in Developing and Developed Regions of Coflow Jets for Highly Diluted Propane", Proc. Combust. Inst, 28, pp.2093~2099 (2000)
- S. H Won, "Normal and Microgravity Experiment of Oscillating Lifted Flames on Coflow", Proc. Combust. Inst, 29, pp.37~44 (2002)
- G. T. Kim, "Flow instability in laminar jet flames driven by alternating crrent electric fields", Proc. Combust. Inst, pp.1~8 (2016)
- M. K. Kim, "Effect of electric fields on the stabilization of premixed laminar Bunsen flames at low AC frequency: Biionic wind effect", Combust. Flame, 159, pp.1151~ (2012)
- N. Peters, "Liftoff characteristics of turbulent jet diffusion flames", AIAA Journal, 21, pp.423~429 (1983)