EXPERIMENTAL STUDY OF THE LENGTH AND STRUCTURE 
OF A FREE-DIFFUSION BURNING-GASES FLAME

Yu. V. Polezhaev,a V. A. Vorob'ev,b 
D. V. Isakov,b G. K. Korovin,b 
I. G. Lozino-Lazinskaya,b I. L. Mostinskii,a
O. G. Stonik,a and R. L. Shiginb

UDC 536.461;536.25

Experimental studies of the length of vertical isolated 
burning flames with hydrogen and methane outflow from cylindrical 
nozzles of diameter 2, 3, 5 and 10 mm into the atmosphere at Re0 = 
100-6800 have been made. The data obtained have been approximated 
by simple calculated dependences. The application of various methods 
for recording the length of a luminous flame (visual, black-and-white 
photography, video and digital cameras) has made it possible to not 
only explain the discrepancies between sizes but also record (at short 
exposures) elementary bending bright cylindrical jets creating, when 
superimposed on the another, one known spindle-shaped form of the flame.

Keywords: combustion, flame, length of burning jets, laminar 
and turbulent regimes. 

aJoint Institute of High Temperatures, Russian Academy of Sciences, 
13/19 Izhorskaya Str., Moscow, 125412, Russia; bM. V. Keldysh Research 
Center, 8 Onezhskaya Str., Moscow, 125438, Russia. Translated from Inzhenerno-
Fizicheskii Zhurnal, Vol. 82, No. 2, pp. 301-307, March-April, 2009. Original 
article submitted May 21, 2008.