Investigation of a plane mixing layer

The results of a study of a plane mixing layer are presented in this paper, the objective being to understand better the role of coherent structures in the mechanisms of entrainment and mixing. The study involved chiefly flow-visualization with simultaneous velocity measurements, with a scheme to synchronize the two, that enables us to get a better picture of the coherent structures which strongly influence the flow. Initial conditions, which are of critical importance in the development of turbulent shear flows, are documented. Mean velocity profiles in the mixing layer and the corresponding spread rate were found to be in general agreement with the range of results of other investigators.