Profiles of the Round Turbulent Jet in A Cross Flow

The shape of a jet issuing normal to a uniform cross wind has been studied experimentally for a large range of jet-to-wind velocity ratios, R, and over a large distance downstream of the source. Photographs taken of an oil aerosol jet were used to determine the size and position of the jet, and mean velocity measurements were made close to the outlet. Dimensional analysis shows that for negligible viscous stresses the jet profile and cross-section size are functions only of R. A momentum flux equation combined with experimental observation leads to a single form for the profile, with all linear dimensions divided by R. Experimental measurements also show that the shape follows the same parameter, and indicate zones of the jet in which the translational and vortex motions dominate. Consequences of the form of the results are discussed.