FLAME PROPAGATION RATES AT REDUCED PRESSURES

The application of the bunsen burner method of measuring flame velocities of gases is extended to liquid fuels by the use of a suitable vaporizer. The bunsen burner nozzle is enclosed and provision made for operation at elevated temperature, reduced pressure or both. The control apparatus which supplies a gaseous or liquid fuel as well as air for combustion is described in detail. The cone angle is obtained by measuring a “schlieren” image of the flame front which has been projected on a screen.

Curves showing flame velocities as a function of air-fuel ratio for natural gas, gasoline, and acetylene are presented. Data were taken for temperature up to 900°F and for pressures down to 3.9″ Hg absolute.