SHAPE COMPLEXITY IN TURBULENCE

The shape complexity of irregular surfaces is quantified by a dimensio nless area-volume measure. A joint distribution of shape complexity an d size is found for level-set islands and lakes in two-dimensional sli ces of the scalar field of liquid-phase turbulent jets, with complexit y values increasing with size. A well-defined power law, over 3 decade s in size (6 decades in area), is found for the shape complexity distr ibution, Such properties are important in various phenomena that rely on large area-volume ratios of surfaces or interfaces, such as turbule nt mixing and combustion. [S0031-9007(97)05126-0].