Laser-Based Multiparameter Measurements

Novel ultraviolet laser-basedmultidimensionalmeasurement techniqueswere applied to the burner exit of a H2 ± air jet engine. Two-dimensionalRayleigh scattering and one-dimensionalRaman scattering were used to measure the mean temperature ® eld, the distributions of the majority species H2 , O2 , H2O, and N2 , and the turbulence intensity distribution 3⁄4T /T in the burner exit plane. The wealth of data allows are elucidation of the turbulent mixing and combustion processes inside the burner. For example, the majority species distributions show that unburned H2 occurred in certain regions in the burner exit plane that were essentially free of O2 and vice versa. This pattern was constant in time. Thismeans that certain ow structures in the burner caused rich mixing in some areas and leanmixing in others, and it explainswhy overall combustionwas not complete in this particular burner.