Fire spread experiments in the field: Temperature and heat fluxes measurements

A measurement device dedicated to the experimental study of wildland fires is presented in this paper. It consists of a thermocouple and two heat flux gauges (radiant and total) fixed on an insulated support. Some data were obtained in the field during a series of four fire spread experiments conducted across various vegetative fuels, ranging from pine needle bed to shrub. The measurement device was located at the top of the vegetation, in the centre of the plots, and data were collected during fire spread in the preheating, flaming and charring regions. The uncertainties of the temperature and heat fluxes measurements, due to radiation or convection, are evaluated. For this range of experiments and in the limit of one-point measurement, radiation from flames is the dominant heat transfer process in the preheating region.

[1]  Charles Baukal,et al.  A review of semi-analytical solutions for flame impingement heat transfer , 1996 .

[2]  Lucile Rossi,et al.  Fire Spread Experiment Across Mediterranean Shrub: Influence of Wind on Flame Front Properties , 2006 .

[3]  Linda G. Blevins,et al.  Modeling of bare and aspirated thermocouples in compartment fires , 1999 .

[4]  Benjamin K. Tsai,et al.  High-heat-flux sensor calibration using black-body radiation , 1998 .

[5]  Frank P. Incropera,et al.  Fundamentals of Heat and Mass Transfer , 1981 .

[6]  D. Latham,et al.  Measurements of radiant emissive power and temperatures in crown fires , 2004 .

[7]  Naim Afgan,et al.  A radiation and convection fluxmeter for high temperature applications , 2000 .

[8]  Begoña C. Arrue,et al.  Gestosa fire spread experiments. , 2002 .

[9]  C A. Womeldorf,et al.  Design and Uncertainty Analysis of a Second-Generation Convective Heat Flux Calibration Facility , 1999, Heat Transfer: Volume 4.

[10]  Alain Degiovanni,et al.  Identification of the upward gas flow velocity and of the geometric characteristics of a flame with a specific thermal sensor , 2005 .

[11]  Ingrid Wetterlund,et al.  Round Robin Study of Total Heat Flux Gauge Calibration at Fire Laboratories , 2004 .

[12]  N. Cheney,et al.  Fire Growth in Grassland Fuels , 1995 .

[13]  William M. Pitts,et al.  Wind effects on fires , 1991 .

[14]  William L. Grosshandler Heat Flux Transducer Calibration: Summary of the 2nd Workshop , 1999 .

[15]  S. Whitaker Forced convection heat transfer correlations for flow in pipes, past flat plates, single cylinders, single spheres, and for flow in packed beds and tube bundles , 1972 .

[16]  G. W. H. Silcock,et al.  A Preliminary Investigation into the Partitioning of the Convective and Radiative Incident Heat Flux in Real Fires , 2006 .

[17]  D. Drysdale An Introduction to Fire Dynamics , 2011 .

[18]  Mingchun Luo,et al.  Effects of Radiation on Temperature Measurement in a Fire Environment , 1997 .

[19]  Benjamin K. Tsai,et al.  High Heat Flux Sensors Calibration Using Blackbody Radiation , 1998 .

[20]  Peter K. Wu Heat Flux Pipe in Large-scale Fire Tests , 2005 .

[21]  R. Chitty,et al.  Some Source-Dependent effects of unbounded fires , 1985 .

[22]  Anil K. Kulkarni,et al.  Analysis of heat flux measurement by circular foil gages in a mixed convection/radiation environment , 1991 .

[23]  Thomas J. Ohlemiller,et al.  Low heat-flux measurements: Some precautions , 1995 .