Scales in the near field of homogeneous turbulent jets*

Turbulent jets are comprised of a cascade of scales, constantly evolving from the instance they are discharged. In previous work, images of the features visible at the turbulent/non-turbulent surface of the opaque jet were used to estimate an interfacial length scale for Re~4,500-50,000. The length scales show monotonic behavior soon after the discharge location. As an extension of that work, planar PIV measurements of the turbulent jets are used to calculate the velocity field and estimate the turbulence kinetic energy, energy dissipation rate, and Taylor microscale throughout the flow field of the homogeneous jets. A comparison of the previous interfacial length scale and the Taylor microscale (at the interface) with respect to their position along the axis of the jet are carried out. We expect to extend the study to non-homogeneous immiscible jets.