Accurate measurements of laminar burning velocity using the Heat Flux method and thermographic phosphor technique

Forskningsoutput: TidskriftsbidragArtikel i vetenskaplig tidskrift

Standard

Accurate measurements of laminar burning velocity using the Heat Flux method and thermographic phosphor technique. / Li, Bo; Lindén, Johannes; Li, Zhongshan; Konnov, Alexander; Aldén, Marcus; de Goey, L. P. H.

I: Proceedings of the Combustion Institute, Vol. 33, 2011, s. 939-946.

Forskningsoutput: TidskriftsbidragArtikel i vetenskaplig tidskrift

Harvard

APA

CBE

MLA

Vancouver

Author

RIS

TY - JOUR

T1 - Accurate measurements of laminar burning velocity using the Heat Flux method and thermographic phosphor technique

AU - Li, Bo

AU - Lindén, Johannes

AU - Li, Zhongshan

AU - Konnov, Alexander

AU - Aldén, Marcus

AU - de Goey, L. P. H.

PY - 2011

Y1 - 2011

N2 - The Heat Flux method was further developed to significantly reduce its experimental uncertainty and used to determine burning velocities under conditions when the net heat loss from the flame to the burner is zero. Non-stretched flames were stabilized on a perforated plate burner at 1 atm. Measurements of the adiabatic burning velocity of methane air flames at initial mixture temperatures of 318 K are presented. Previously, tiny thermocouples in the thin burner plate were used to evaluate when the heat flux of the flame to the burner is zero. Related errors limit the accuracy of the method so far. A new experimental procedure based on thermographic phosphors is described which avoids these errors. The new experimental procedure is described. An UV thermographic phosphor ZnO:Zn was selected and used to sensitively control the temperature uniformity on the burner plate to within 60 mK. Uncertainties of the measurements were analyzed and assessed experimentally. A more accurate evaluation of the gas velocities, using mass weighting, was introduced to increase the accuracy further. The uncertainty of the measured adiabatic burning velocities due to the temperature scattering can be reduced from typically +/-1.5 cm s at Phi = 0.7 methane air flame to +/-0.25 cm s. The overall accuracy of the burning velocities including the uncertainty from the employed mass flow controllers was evaluated to be better than +/-0.35 cm s. Possibilities to further improve the measurement accuracy are discussed with practical considerations. (C) 2010 The Combustion Institute. Published by Elsevier Inc. All rights reserved.

AB - The Heat Flux method was further developed to significantly reduce its experimental uncertainty and used to determine burning velocities under conditions when the net heat loss from the flame to the burner is zero. Non-stretched flames were stabilized on a perforated plate burner at 1 atm. Measurements of the adiabatic burning velocity of methane air flames at initial mixture temperatures of 318 K are presented. Previously, tiny thermocouples in the thin burner plate were used to evaluate when the heat flux of the flame to the burner is zero. Related errors limit the accuracy of the method so far. A new experimental procedure based on thermographic phosphors is described which avoids these errors. The new experimental procedure is described. An UV thermographic phosphor ZnO:Zn was selected and used to sensitively control the temperature uniformity on the burner plate to within 60 mK. Uncertainties of the measurements were analyzed and assessed experimentally. A more accurate evaluation of the gas velocities, using mass weighting, was introduced to increase the accuracy further. The uncertainty of the measured adiabatic burning velocities due to the temperature scattering can be reduced from typically +/-1.5 cm s at Phi = 0.7 methane air flame to +/-0.25 cm s. The overall accuracy of the burning velocities including the uncertainty from the employed mass flow controllers was evaluated to be better than +/-0.35 cm s. Possibilities to further improve the measurement accuracy are discussed with practical considerations. (C) 2010 The Combustion Institute. Published by Elsevier Inc. All rights reserved.

KW - Burning velocity

KW - Heat Flux method

KW - Thermographic phosphor

U2 - 10.1016/j.proci.2010.06.111

DO - 10.1016/j.proci.2010.06.111

M3 - Article

VL - 33

SP - 939

EP - 946

JO - Proceedings of the Combustion Institute

JF - Proceedings of the Combustion Institute

SN - 1540-7489

ER -