The effect of flow conditions on the geometry of the turbulent Bunsen flame was investigated. Turbulent flame speed is defines in terms of flame geometry, and data are presented showing the effect of Reynolds Number of flow in the range of 3000 to 35,000 on flame speed for burner diameters from 14 to 1-18 in. for three fuels acetylene, ethylene, and propane. The normal flame speed of an explosive mixture was shown to be an important factor in determining its turbulent flame speed. The turbulent flame speed is a function of both the Reynolds Number of the turbulent flow in the burner tube and of the tube diameter.