Short Communication

An optical study of tbe interaction of a laminar, premixed, rod stabilized flame and a Karman vortex street has been performed. The technique used was laser tomography, in which the unburned gases are seeded with a silicone oil spray and then illuminated with a sheet of laser light. The oil spray evaporates and disappears in passing through the flame, making possible the high speed cinematography of the structure of the flame sheet. The wavelength and frequency of the perturbed flame motion is found to correspond closely to that of the vortex street, allowing a simple phenomenological explanation of the cyclic behavior of the flame.