ABSTRACT
In this chapter, we review the latest research activities concerning wakes generated by bodies moving in stratiŸed žuids and resulting wake “signatures” which are of importance in designing, detecting, and stealth of large underwater dirigibles. Special attention will be given to surface signatures of wakes, their longevity and survival in background conditions (shear, turbulence) typical of the upper ocean. ›e emphasis is mostly on late or far wakes of self-propelled bodies in steady and unsteady motion. In the latter case, large (much larger than the body size) pancake eddies become important which dynamics are also discussed. To make the material self-su®cient, the general problem of žows generated by localized forcing is also formulated. Di§erent aspects of such žows were studied in the past by using mostly laboratory experiments and theoretical analysis. Besides scientiŸc interest, these basic žows have applications related to stratiŸed wakes, oceanic mushroom-like currents, atmospheric/oceanic jets and quasi-2D, geophysical, turbulence. Because of strict space limitations, results of numerical simulations were not included into this brief review.
