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This report documents a series of time-averaged gas species measurements made along the centerline of methanol, ethanol, acetone, and methane pool fires steadily burning in a quiescent environment. All gas species measurements are obtained using a Gas Chromatograph/ Mass Spectrometer System (GC/MS) for gas samples extracted at various heights above the fire and repeated at least twice at each location. Gas species volume fractions are determined via the GC/MS using predetermined calibration factors. Soot mass fractions are simultaneously measured during the gas sampling process. The gas species volume and soot mass fractions are compared at different heights within the fire and across a variety of different fuels. Other fire parameters are measured as well, including time-averaged temperature measurements and mass burning rates.

A series of measurements was conducted to characterize the structure of a 1 m diameter methanol pool fire steadily burning with a constant lip height in a well-ventilated quiescent environment. Time-averaged local measurements of gas-phase temperature were conducted using 50 μm diameter, Type S, bare wire, thermocouples with a bead that was approximately spherical with a diameter of about 150 μm. The thermocouple bead temperature was corrected for radiative loss and thermal inertia effects. The contribution of the radiative loss correction and thermal inertia correction terms to uncertainty of the gas velocity was analyzed. A simulation of the 1 m methanol pool fire was conducted using the Fire Dynamics Simulator (FDS) to obtain the gas velocity distribution above the burner which helped correct the thermocouple temperature measurement to obtain the gas temperature. The gas temperature distribution profile above the burner centerline was compared to previous studies of a 30 cm methanol fire. The maximum mean gas temperature was 1371 K, which occurred 30 cm above the burner on the centerline. Careful analysis determined that the average combined uncertainty of the mean and the standard deviation of the measured gas temperature was 5 % and 26 %, respectively. The actual heat release rate was measured using oxygen consumption calorimetry and compared favorably with the ideal heat release rate calculated from the measured mass burning rate. The heat flux distribution about the pool fire was measured using fourteen wide-angle view, water-cooled, Gardon-type, total heat flux gauges. The radiative emission from the fire was estimated by considering the radiative heat flux through a virtual cylinder about the fire and by a single point estimate. The radiative emission measurements coupled with the mass loss measurement allowed determination of the radiative fraction, which was equal to 0.22 ± 16 % and 0.20 ± 34 % for the multi-location and single-location measurements, respectively. Flame characteristics, such as, the mean flame height, pulsation frequency and the flame instability near the fuel surface, were analyzed using the 30 Hz video record of the fire. The mean flame height was measured as 1.10 m ± 0.22 m above the burner rim and the puffing frequency was about 1.37 Hz, which was consistent with a Fourier analysis of the transient thermocouple measurements (=1.39 Hz ± 0.013 Hz). The pool surface temperature was measured to be nearly the fuel boiling point.

Summary This study documents a series of time‐averaged gas species measurements made along the centerline of a 30 cm methanol pool fire steadily burning in a quiescent environment. All gas species measurements were obtained using a gas chromatograph/mass spectrometer system (GC/MS). Measurements were made at different heights along the centerline of the fire and repeated at least twice for each location. Gas species volume fractions were determined via the GC/MS using predetermined calibration factors. The gas species volume fractions were compared at different heights within the methanol fire.