Physica D Nonlinear Phenomena, Special Issue on Small Scale Turbulence

This special issue was conceived as a commentary on small scale turbulence—in particular, on how it depends on large scales and the global dynamics, as a whole, of the flow in question. The focus on the interaction between small and large scales has revitalized research into turbulence, and it does not necessarily imply the fallacy of universality. On the other hand, these interactions have serious practical implications—for example, for methods of large eddy simulations (LES) and our understanding of turbulent combustion. Since multiscale systems are ubiquitous in nature and technology, the exploration of the interaction between large and small scales has a generic value in contemporary science. A broad knowledge of neighboring fields can often be of great help and a great inspiration. Indeed, many fields have now matured to a state beyond which the traditionally subdivided large and small scales are thought to interact only in a limited way. Two examples suffice. First, it is now known that the cancerous behavior in space and time of biological organisms is the result of nonlinear interactions among tumor cells and their microenvironment, on the one hand, and the neoplastic growth at the tissue level, on the other. Similarly, the cosmological parameters of massive, multicomponent and quasi-equilibrium clusters are related to the expanding large scale phenomena. The preparation of this special issue began in August 2010. Since then, more than twenty papers have been received—many focusing on various aspects of small scale dynamics, others discussing correlations with the large scale. We decided not to be too restrictive in our interpretation, since excursiveness can indeed be fruitful to a certain degree. The papers of the special issue can be grouped roughly into the following themes. We comment only briefly on the papers themselves and invite the reader’s attention to the original papers themselves. http://www.sciencedirect.com/science/journal/01672789/241/